perf tools: Introduce tools/lib/lk library

[mirror_ubuntu-bionic-kernel.git] / tools / perf / util / probe-event.c

/*
 * probe-event.c : perf-probe definition to probe_events format converter
 *
 * Written by Masami Hiramatsu <mhiramat@redhat.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 */

#include <sys/utsname.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <limits.h>
#include <elf.h>

#include "util.h"
#include "event.h"
#include "strlist.h"
#include "debug.h"
#include "cache.h"
#include "color.h"
#include "symbol.h"
#include "thread.h"
#include <lk/debugfs.h>
#include "trace-event.h"        /* For __maybe_unused */
#include "probe-event.h"
#include "probe-finder.h"
#include "session.h"

#define MAX_CMDLEN 256
#define MAX_PROBE_ARGS 128
#define PERFPROBE_GROUP "probe"

bool probe_event_dry_run;       /* Dry run flag */

#define semantic_error(msg ...) pr_err("Semantic error :" msg)

/* If there is no space to write, returns -E2BIG. */
static int e_snprintf(char *str, size_t size, const char *format, ...)
        __attribute__((format(printf, 3, 4)));

static int e_snprintf(char *str, size_t size, const char *format, ...)
{
        int ret;
        va_list ap;
        va_start(ap, format);
        ret = vsnprintf(str, size, format, ap);
        va_end(ap);
        if (ret >= (int)size)
                ret = -E2BIG;
        return ret;
}

static char *synthesize_perf_probe_point(struct perf_probe_point *pp);
static int convert_name_to_addr(struct perf_probe_event *pev,
                                const char *exec);
static struct machine machine;

/* Initialize symbol maps and path of vmlinux/modules */
static int init_vmlinux(void)
{
        int ret;

        symbol_conf.sort_by_name = true;
        if (symbol_conf.vmlinux_name == NULL)
                symbol_conf.try_vmlinux_path = true;
        else
                pr_debug("Use vmlinux: %s\n", symbol_conf.vmlinux_name);
        ret = symbol__init();
        if (ret < 0) {
                pr_debug("Failed to init symbol map.\n");
                goto out;
        }

        ret = machine__init(&machine, "", HOST_KERNEL_ID);
        if (ret < 0)
                goto out;

        if (machine__create_kernel_maps(&machine) < 0) {
                pr_debug("machine__create_kernel_maps() failed.\n");
                goto out;
        }
out:
        if (ret < 0)
                pr_warning("Failed to init vmlinux path.\n");
        return ret;
}

static struct symbol *__find_kernel_function_by_name(const char *name,
                                                     struct map **mapp)
{
        return machine__find_kernel_function_by_name(&machine, name, mapp,
                                                     NULL);
}

static struct map *kernel_get_module_map(const char *module)
{
        struct rb_node *nd;
        struct map_groups *grp = &machine.kmaps;

        /* A file path -- this is an offline module */
        if (module && strchr(module, '/'))
                return machine__new_module(&machine, 0, module);

        if (!module)
                module = "kernel";

        for (nd = rb_first(&grp->maps[MAP__FUNCTION]); nd; nd = rb_next(nd)) {
                struct map *pos = rb_entry(nd, struct map, rb_node);
                if (strncmp(pos->dso->short_name + 1, module,
                            pos->dso->short_name_len - 2) == 0) {
                        return pos;
                }
        }
        return NULL;
}

static struct dso *kernel_get_module_dso(const char *module)
{
        struct dso *dso;
        struct map *map;
        const char *vmlinux_name;

        if (module) {
                list_for_each_entry(dso, &machine.kernel_dsos, node) {
                        if (strncmp(dso->short_name + 1, module,
                                    dso->short_name_len - 2) == 0)
                                goto found;
                }
                pr_debug("Failed to find module %s.\n", module);
                return NULL;
        }

        map = machine.vmlinux_maps[MAP__FUNCTION];
        dso = map->dso;

        vmlinux_name = symbol_conf.vmlinux_name;
        if (vmlinux_name) {
                if (dso__load_vmlinux(dso, map, vmlinux_name, NULL) <= 0)
                        return NULL;
        } else {
                if (dso__load_vmlinux_path(dso, map, NULL) <= 0) {
                        pr_debug("Failed to load kernel map.\n");
                        return NULL;
                }
        }
found:
        return dso;
}

const char *kernel_get_module_path(const char *module)
{
        struct dso *dso = kernel_get_module_dso(module);
        return (dso) ? dso->long_name : NULL;
}

static int init_user_exec(void)
{
        int ret = 0;

        symbol_conf.try_vmlinux_path = false;
        symbol_conf.sort_by_name = true;
        ret = symbol__init();

        if (ret < 0)
                pr_debug("Failed to init symbol map.\n");

        return ret;
}

static int convert_to_perf_probe_point(struct probe_trace_point *tp,
                                        struct perf_probe_point *pp)
{
        pp->function = strdup(tp->symbol);

        if (pp->function == NULL)
                return -ENOMEM;

        pp->offset = tp->offset;
        pp->retprobe = tp->retprobe;

        return 0;
}

#ifdef DWARF_SUPPORT
/* Open new debuginfo of given module */
static struct debuginfo *open_debuginfo(const char *module)
{
        const char *path;

        /* A file path -- this is an offline module */
        if (module && strchr(module, '/'))
                path = module;
        else {
                path = kernel_get_module_path(module);

                if (!path) {
                        pr_err("Failed to find path of %s module.\n",
                               module ?: "kernel");
                        return NULL;
                }
        }
        return debuginfo__new(path);
}

/*
 * Convert trace point to probe point with debuginfo
 * Currently only handles kprobes.
 */
static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp,
                                        struct perf_probe_point *pp)
{
        struct symbol *sym;
        struct map *map;
        u64 addr;
        int ret = -ENOENT;
        struct debuginfo *dinfo;

        sym = __find_kernel_function_by_name(tp->symbol, &map);
        if (sym) {
                addr = map->unmap_ip(map, sym->start + tp->offset);
                pr_debug("try to find %s+%ld@%" PRIx64 "\n", tp->symbol,
                         tp->offset, addr);

                dinfo = debuginfo__new_online_kernel(addr);
                if (dinfo) {
                        ret = debuginfo__find_probe_point(dinfo,
                                                 (unsigned long)addr, pp);
                        debuginfo__delete(dinfo);
                } else {
                        pr_debug("Failed to open debuginfo at 0x%" PRIx64 "\n",
                                 addr);
                        ret = -ENOENT;
                }
        }
        if (ret <= 0) {
                pr_debug("Failed to find corresponding probes from "
                         "debuginfo. Use kprobe event information.\n");
                return convert_to_perf_probe_point(tp, pp);
        }
        pp->retprobe = tp->retprobe;

        return 0;
}

static int add_module_to_probe_trace_events(struct probe_trace_event *tevs,
                                            int ntevs, const char *module)
{
        int i, ret = 0;
        char *tmp;

        if (!module)
                return 0;

        tmp = strrchr(module, '/');
        if (tmp) {
                /* This is a module path -- get the module name */
                module = strdup(tmp + 1);
                if (!module)
                        return -ENOMEM;
                tmp = strchr(module, '.');
                if (tmp)
                        *tmp = '\0';
                tmp = (char *)module;   /* For free() */
        }

        for (i = 0; i < ntevs; i++) {
                tevs[i].point.module = strdup(module);
                if (!tevs[i].point.module) {
                        ret = -ENOMEM;
                        break;
                }
        }

        if (tmp)
                free(tmp);

        return ret;
}

/* Try to find perf_probe_event with debuginfo */
static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
                                          struct probe_trace_event **tevs,
                                          int max_tevs, const char *target)
{
        bool need_dwarf = perf_probe_event_need_dwarf(pev);
        struct debuginfo *dinfo;
        int ntevs, ret = 0;

        if (pev->uprobes) {
                if (need_dwarf) {
                        pr_warning("Debuginfo-analysis is not yet supported"
                                        " with -x/--exec option.\n");
                        return -ENOSYS;
                }
                return convert_name_to_addr(pev, target);
        }

        dinfo = open_debuginfo(target);

        if (!dinfo) {
                if (need_dwarf) {
                        pr_warning("Failed to open debuginfo file.\n");
                        return -ENOENT;
                }
                pr_debug("Could not open debuginfo. Try to use symbols.\n");
                return 0;
        }

        /* Searching trace events corresponding to a probe event */
        ntevs = debuginfo__find_trace_events(dinfo, pev, tevs, max_tevs);

        debuginfo__delete(dinfo);

        if (ntevs > 0) {        /* Succeeded to find trace events */
                pr_debug("find %d probe_trace_events.\n", ntevs);
                if (target)
                        ret = add_module_to_probe_trace_events(*tevs, ntevs,
                                                               target);
                return ret < 0 ? ret : ntevs;
        }

        if (ntevs == 0) {       /* No error but failed to find probe point. */
                pr_warning("Probe point '%s' not found.\n",
                           synthesize_perf_probe_point(&pev->point));
                return -ENOENT;
        }
        /* Error path : ntevs < 0 */
        pr_debug("An error occurred in debuginfo analysis (%d).\n", ntevs);
        if (ntevs == -EBADF) {
                pr_warning("Warning: No dwarf info found in the vmlinux - "
                        "please rebuild kernel with CONFIG_DEBUG_INFO=y.\n");
                if (!need_dwarf) {
                        pr_debug("Trying to use symbols.\n");
                        return 0;
                }
        }
        return ntevs;
}

/*
 * Find a src file from a DWARF tag path. Prepend optional source path prefix
 * and chop off leading directories that do not exist. Result is passed back as
 * a newly allocated path on success.
 * Return 0 if file was found and readable, -errno otherwise.
 */
static int get_real_path(const char *raw_path, const char *comp_dir,
                         char **new_path)
{
        const char *prefix = symbol_conf.source_prefix;

        if (!prefix) {
                if (raw_path[0] != '/' && comp_dir)
                        /* If not an absolute path, try to use comp_dir */
                        prefix = comp_dir;
                else {
                        if (access(raw_path, R_OK) == 0) {
                                *new_path = strdup(raw_path);
                                return 0;
                        } else
                                return -errno;
                }
        }

        *new_path = malloc((strlen(prefix) + strlen(raw_path) + 2));
        if (!*new_path)
                return -ENOMEM;

        for (;;) {
                sprintf(*new_path, "%s/%s", prefix, raw_path);

                if (access(*new_path, R_OK) == 0)
                        return 0;

                if (!symbol_conf.source_prefix)
                        /* In case of searching comp_dir, don't retry */
                        return -errno;

                switch (errno) {
                case ENAMETOOLONG:
                case ENOENT:
                case EROFS:
                case EFAULT:
                        raw_path = strchr(++raw_path, '/');
                        if (!raw_path) {
                                free(*new_path);
                                *new_path = NULL;
                                return -ENOENT;
                        }
                        continue;

                default:
                        free(*new_path);
                        *new_path = NULL;
                        return -errno;
                }
        }
}

#define LINEBUF_SIZE 256
#define NR_ADDITIONAL_LINES 2

static int __show_one_line(FILE *fp, int l, bool skip, bool show_num)
{
        char buf[LINEBUF_SIZE];
        const char *color = show_num ? "" : PERF_COLOR_BLUE;
        const char *prefix = NULL;

        do {
                if (fgets(buf, LINEBUF_SIZE, fp) == NULL)
                        goto error;
                if (skip)
                        continue;
                if (!prefix) {
                        prefix = show_num ? "%7d  " : "         ";
                        color_fprintf(stdout, color, prefix, l);
                }
                color_fprintf(stdout, color, "%s", buf);

        } while (strchr(buf, '\n') == NULL);

        return 1;
error:
        if (ferror(fp)) {
                pr_warning("File read error: %s\n", strerror(errno));
                return -1;
        }
        return 0;
}

static int _show_one_line(FILE *fp, int l, bool skip, bool show_num)
{
        int rv = __show_one_line(fp, l, skip, show_num);
        if (rv == 0) {
                pr_warning("Source file is shorter than expected.\n");
                rv = -1;
        }
        return rv;
}

#define show_one_line_with_num(f,l)     _show_one_line(f,l,false,true)
#define show_one_line(f,l)              _show_one_line(f,l,false,false)
#define skip_one_line(f,l)              _show_one_line(f,l,true,false)
#define show_one_line_or_eof(f,l)       __show_one_line(f,l,false,false)

/*
 * Show line-range always requires debuginfo to find source file and
 * line number.
 */
int show_line_range(struct line_range *lr, const char *module)
{
        int l = 1;
        struct line_node *ln;
        struct debuginfo *dinfo;
        FILE *fp;
        int ret;
        char *tmp;

        /* Search a line range */
        ret = init_vmlinux();
        if (ret < 0)
                return ret;

        dinfo = open_debuginfo(module);
        if (!dinfo) {
                pr_warning("Failed to open debuginfo file.\n");
                return -ENOENT;
        }

        ret = debuginfo__find_line_range(dinfo, lr);
        debuginfo__delete(dinfo);
        if (ret == 0) {
                pr_warning("Specified source line is not found.\n");
                return -ENOENT;
        } else if (ret < 0) {
                pr_warning("Debuginfo analysis failed. (%d)\n", ret);
                return ret;
        }

        /* Convert source file path */
        tmp = lr->path;
        ret = get_real_path(tmp, lr->comp_dir, &lr->path);
        free(tmp);      /* Free old path */
        if (ret < 0) {
                pr_warning("Failed to find source file. (%d)\n", ret);
                return ret;
        }

        setup_pager();

        if (lr->function)
                fprintf(stdout, "<%s@%s:%d>\n", lr->function, lr->path,
                        lr->start - lr->offset);
        else
                fprintf(stdout, "<%s:%d>\n", lr->path, lr->start);

        fp = fopen(lr->path, "r");
        if (fp == NULL) {
                pr_warning("Failed to open %s: %s\n", lr->path,
                           strerror(errno));
                return -errno;
        }
        /* Skip to starting line number */
        while (l < lr->start) {
                ret = skip_one_line(fp, l++);
                if (ret < 0)
                        goto end;
        }

        list_for_each_entry(ln, &lr->line_list, list) {
                for (; ln->line > l; l++) {
                        ret = show_one_line(fp, l - lr->offset);
                        if (ret < 0)
                                goto end;
                }
                ret = show_one_line_with_num(fp, l++ - lr->offset);
                if (ret < 0)
                        goto end;
        }

        if (lr->end == INT_MAX)
                lr->end = l + NR_ADDITIONAL_LINES;
        while (l <= lr->end) {
                ret = show_one_line_or_eof(fp, l++ - lr->offset);
                if (ret <= 0)
                        break;
        }
end:
        fclose(fp);
        return ret;
}

static int show_available_vars_at(struct debuginfo *dinfo,
                                  struct perf_probe_event *pev,
                                  int max_vls, struct strfilter *_filter,
                                  bool externs)
{
        char *buf;
        int ret, i, nvars;
        struct str_node *node;
        struct variable_list *vls = NULL, *vl;
        const char *var;

        buf = synthesize_perf_probe_point(&pev->point);
        if (!buf)
                return -EINVAL;
        pr_debug("Searching variables at %s\n", buf);

        ret = debuginfo__find_available_vars_at(dinfo, pev, &vls,
                                                max_vls, externs);
        if (ret <= 0) {
                pr_err("Failed to find variables at %s (%d)\n", buf, ret);
                goto end;
        }
        /* Some variables are found */
        fprintf(stdout, "Available variables at %s\n", buf);
        for (i = 0; i < ret; i++) {
                vl = &vls[i];
                /*
                 * A probe point might be converted to
                 * several trace points.
                 */
                fprintf(stdout, "\t@<%s+%lu>\n", vl->point.symbol,
                        vl->point.offset);
                free(vl->point.symbol);
                nvars = 0;
                if (vl->vars) {
                        strlist__for_each(node, vl->vars) {
                                var = strchr(node->s, '\t') + 1;
                                if (strfilter__compare(_filter, var)) {
                                        fprintf(stdout, "\t\t%s\n", node->s);
                                        nvars++;
                                }
                        }
                        strlist__delete(vl->vars);
                }
                if (nvars == 0)
                        fprintf(stdout, "\t\t(No matched variables)\n");
        }
        free(vls);
end:
        free(buf);
        return ret;
}

/* Show available variables on given probe point */
int show_available_vars(struct perf_probe_event *pevs, int npevs,
                        int max_vls, const char *module,
                        struct strfilter *_filter, bool externs)
{
        int i, ret = 0;
        struct debuginfo *dinfo;

        ret = init_vmlinux();
        if (ret < 0)
                return ret;

        dinfo = open_debuginfo(module);
        if (!dinfo) {
                pr_warning("Failed to open debuginfo file.\n");
                return -ENOENT;
        }

        setup_pager();

        for (i = 0; i < npevs && ret >= 0; i++)
                ret = show_available_vars_at(dinfo, &pevs[i], max_vls, _filter,
                                             externs);

        debuginfo__delete(dinfo);
        return ret;
}

#else   /* !DWARF_SUPPORT */

static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp,
                                        struct perf_probe_point *pp)
{
        struct symbol *sym;

        sym = __find_kernel_function_by_name(tp->symbol, NULL);
        if (!sym) {
                pr_err("Failed to find symbol %s in kernel.\n", tp->symbol);
                return -ENOENT;
        }

        return convert_to_perf_probe_point(tp, pp);
}

static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
                                struct probe_trace_event **tevs __maybe_unused,
                                int max_tevs __maybe_unused, const char *target)
{
        if (perf_probe_event_need_dwarf(pev)) {
                pr_warning("Debuginfo-analysis is not supported.\n");
                return -ENOSYS;
        }

        if (pev->uprobes)
                return convert_name_to_addr(pev, target);

        return 0;
}

int show_line_range(struct line_range *lr __maybe_unused,
                    const char *module __maybe_unused)
{
        pr_warning("Debuginfo-analysis is not supported.\n");
        return -ENOSYS;
}

int show_available_vars(struct perf_probe_event *pevs __maybe_unused,
                        int npevs __maybe_unused, int max_vls __maybe_unused,
                        const char *module __maybe_unused,
                        struct strfilter *filter __maybe_unused,
                        bool externs __maybe_unused)
{
        pr_warning("Debuginfo-analysis is not supported.\n");
        return -ENOSYS;
}
#endif

static int parse_line_num(char **ptr, int *val, const char *what)
{
        const char *start = *ptr;

        errno = 0;
        *val = strtol(*ptr, ptr, 0);
        if (errno || *ptr == start) {
                semantic_error("'%s' is not a valid number.\n", what);
                return -EINVAL;
        }
        return 0;
}

/*
 * Stuff 'lr' according to the line range described by 'arg'.
 * The line range syntax is described by:
 *
 *         SRC[:SLN[+NUM|-ELN]]
 *         FNC[@SRC][:SLN[+NUM|-ELN]]
 */
int parse_line_range_desc(const char *arg, struct line_range *lr)
{
        char *range, *file, *name = strdup(arg);
        int err;

        if (!name)
                return -ENOMEM;

        lr->start = 0;
        lr->end = INT_MAX;

        range = strchr(name, ':');
        if (range) {
                *range++ = '\0';

                err = parse_line_num(&range, &lr->start, "start line");
                if (err)
                        goto err;

                if (*range == '+' || *range == '-') {
                        const char c = *range++;

                        err = parse_line_num(&range, &lr->end, "end line");
                        if (err)
                                goto err;

                        if (c == '+') {
                                lr->end += lr->start;
                                /*
                                 * Adjust the number of lines here.
                                 * If the number of lines == 1, the
                                 * the end of line should be equal to
                                 * the start of line.
                                 */
                                lr->end--;
                        }
                }

                pr_debug("Line range is %d to %d\n", lr->start, lr->end);

                err = -EINVAL;
                if (lr->start > lr->end) {
                        semantic_error("Start line must be smaller"
                                       " than end line.\n");
                        goto err;
                }
                if (*range != '\0') {
                        semantic_error("Tailing with invalid str '%s'.\n", range);
                        goto err;
                }
        }

        file = strchr(name, '@');
        if (file) {
                *file = '\0';
                lr->file = strdup(++file);
                if (lr->file == NULL) {
                        err = -ENOMEM;
                        goto err;
                }
                lr->function = name;
        } else if (strchr(name, '.'))
                lr->file = name;
        else
                lr->function = name;

        return 0;
err:
        free(name);
        return err;
}

/* Check the name is good for event/group */
static bool check_event_name(const char *name)
{
        if (!isalpha(*name) && *name != '_')
                return false;
        while (*++name != '\0') {
                if (!isalpha(*name) && !isdigit(*name) && *name != '_')
                        return false;
        }
        return true;
}

/* Parse probepoint definition. */
static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev)
{
        struct perf_probe_point *pp = &pev->point;
        char *ptr, *tmp;
        char c, nc = 0;
        /*
         * <Syntax>
         * perf probe [EVENT=]SRC[:LN|;PTN]
         * perf probe [EVENT=]FUNC[@SRC][+OFFS|%return|:LN|;PAT]
         *
         * TODO:Group name support
         */

        ptr = strpbrk(arg, ";=@+%");
        if (ptr && *ptr == '=') {       /* Event name */
                *ptr = '\0';
                tmp = ptr + 1;
                if (strchr(arg, ':')) {
                        semantic_error("Group name is not supported yet.\n");
                        return -ENOTSUP;
                }
                if (!check_event_name(arg)) {
                        semantic_error("%s is bad for event name -it must "
                                       "follow C symbol-naming rule.\n", arg);
                        return -EINVAL;
                }
                pev->event = strdup(arg);
                if (pev->event == NULL)
                        return -ENOMEM;
                pev->group = NULL;
                arg = tmp;
        }

        ptr = strpbrk(arg, ";:+@%");
        if (ptr) {
                nc = *ptr;
                *ptr++ = '\0';
        }

        tmp = strdup(arg);
        if (tmp == NULL)
                return -ENOMEM;

        /* Check arg is function or file and copy it */
        if (strchr(tmp, '.'))   /* File */
                pp->file = tmp;
        else                    /* Function */
                pp->function = tmp;

        /* Parse other options */
        while (ptr) {
                arg = ptr;
                c = nc;
                if (c == ';') { /* Lazy pattern must be the last part */
                        pp->lazy_line = strdup(arg);
                        if (pp->lazy_line == NULL)
                                return -ENOMEM;
                        break;
                }
                ptr = strpbrk(arg, ";:+@%");
                if (ptr) {
                        nc = *ptr;
                        *ptr++ = '\0';
                }
                switch (c) {
                case ':':       /* Line number */
                        pp->line = strtoul(arg, &tmp, 0);
                        if (*tmp != '\0') {
                                semantic_error("There is non-digit char"
                                               " in line number.\n");
                                return -EINVAL;
                        }
                        break;
                case '+':       /* Byte offset from a symbol */
                        pp->offset = strtoul(arg, &tmp, 0);
                        if (*tmp != '\0') {
                                semantic_error("There is non-digit character"
                                                " in offset.\n");
                                return -EINVAL;
                        }
                        break;
                case '@':       /* File name */
                        if (pp->file) {
                                semantic_error("SRC@SRC is not allowed.\n");
                                return -EINVAL;
                        }
                        pp->file = strdup(arg);
                        if (pp->file == NULL)
                                return -ENOMEM;
                        break;
                case '%':       /* Probe places */
                        if (strcmp(arg, "return") == 0) {
                                pp->retprobe = 1;
                        } else {        /* Others not supported yet */
                                semantic_error("%%%s is not supported.\n", arg);
                                return -ENOTSUP;
                        }
                        break;
                default:        /* Buggy case */
                        pr_err("This program has a bug at %s:%d.\n",
                                __FILE__, __LINE__);
                        return -ENOTSUP;
                        break;
                }
        }

        /* Exclusion check */
        if (pp->lazy_line && pp->line) {
                semantic_error("Lazy pattern can't be used with"
                               " line number.\n");
                return -EINVAL;
        }

        if (pp->lazy_line && pp->offset) {
                semantic_error("Lazy pattern can't be used with offset.\n");
                return -EINVAL;
        }

        if (pp->line && pp->offset) {
                semantic_error("Offset can't be used with line number.\n");
                return -EINVAL;
        }

        if (!pp->line && !pp->lazy_line && pp->file && !pp->function) {
                semantic_error("File always requires line number or "
                               "lazy pattern.\n");
                return -EINVAL;
        }

        if (pp->offset && !pp->function) {
                semantic_error("Offset requires an entry function.\n");
                return -EINVAL;
        }

        if (pp->retprobe && !pp->function) {
                semantic_error("Return probe requires an entry function.\n");
                return -EINVAL;
        }

        if ((pp->offset || pp->line || pp->lazy_line) && pp->retprobe) {
                semantic_error("Offset/Line/Lazy pattern can't be used with "
                               "return probe.\n");
                return -EINVAL;
        }

        pr_debug("symbol:%s file:%s line:%d offset:%lu return:%d lazy:%s\n",
                 pp->function, pp->file, pp->line, pp->offset, pp->retprobe,
                 pp->lazy_line);
        return 0;
}

/* Parse perf-probe event argument */
static int parse_perf_probe_arg(char *str, struct perf_probe_arg *arg)
{
        char *tmp, *goodname;
        struct perf_probe_arg_field **fieldp;

        pr_debug("parsing arg: %s into ", str);

        tmp = strchr(str, '=');
        if (tmp) {
                arg->name = strndup(str, tmp - str);
                if (arg->name == NULL)
                        return -ENOMEM;
                pr_debug("name:%s ", arg->name);
                str = tmp + 1;
        }

        tmp = strchr(str, ':');
        if (tmp) {      /* Type setting */
                *tmp = '\0';
                arg->type = strdup(tmp + 1);
                if (arg->type == NULL)
                        return -ENOMEM;
                pr_debug("type:%s ", arg->type);
        }

        tmp = strpbrk(str, "-.[");
        if (!is_c_varname(str) || !tmp) {
                /* A variable, register, symbol or special value */
                arg->var = strdup(str);
                if (arg->var == NULL)
                        return -ENOMEM;
                pr_debug("%s\n", arg->var);
                return 0;
        }

        /* Structure fields or array element */
        arg->var = strndup(str, tmp - str);
        if (arg->var == NULL)
                return -ENOMEM;
        goodname = arg->var;
        pr_debug("%s, ", arg->var);
        fieldp = &arg->field;

        do {
                *fieldp = zalloc(sizeof(struct perf_probe_arg_field));
                if (*fieldp == NULL)
                        return -ENOMEM;
                if (*tmp == '[') {      /* Array */
                        str = tmp;
                        (*fieldp)->index = strtol(str + 1, &tmp, 0);
                        (*fieldp)->ref = true;
                        if (*tmp != ']' || tmp == str + 1) {
                                semantic_error("Array index must be a"
                                                " number.\n");
                                return -EINVAL;
                        }
                        tmp++;
                        if (*tmp == '\0')
                                tmp = NULL;
                } else {                /* Structure */
                        if (*tmp == '.') {
                                str = tmp + 1;
                                (*fieldp)->ref = false;
                        } else if (tmp[1] == '>') {
                                str = tmp + 2;
                                (*fieldp)->ref = true;
                        } else {
                                semantic_error("Argument parse error: %s\n",
                                               str);
                                return -EINVAL;
                        }
                        tmp = strpbrk(str, "-.[");
                }
                if (tmp) {
                        (*fieldp)->name = strndup(str, tmp - str);
                        if ((*fieldp)->name == NULL)
                                return -ENOMEM;
                        if (*str != '[')
                                goodname = (*fieldp)->name;
                        pr_debug("%s(%d), ", (*fieldp)->name, (*fieldp)->ref);
                        fieldp = &(*fieldp)->next;
                }
        } while (tmp);
        (*fieldp)->name = strdup(str);
        if ((*fieldp)->name == NULL)
                return -ENOMEM;
        if (*str != '[')
                goodname = (*fieldp)->name;
        pr_debug("%s(%d)\n", (*fieldp)->name, (*fieldp)->ref);

        /* If no name is specified, set the last field name (not array index)*/
        if (!arg->name) {
                arg->name = strdup(goodname);
                if (arg->name == NULL)
                        return -ENOMEM;
        }
        return 0;
}

/* Parse perf-probe event command */
int parse_perf_probe_command(const char *cmd, struct perf_probe_event *pev)
{
        char **argv;
        int argc, i, ret = 0;

        argv = argv_split(cmd, &argc);
        if (!argv) {
                pr_debug("Failed to split arguments.\n");
                return -ENOMEM;
        }
        if (argc - 1 > MAX_PROBE_ARGS) {
                semantic_error("Too many probe arguments (%d).\n", argc - 1);
                ret = -ERANGE;
                goto out;
        }
        /* Parse probe point */
        ret = parse_perf_probe_point(argv[0], pev);
        if (ret < 0)
                goto out;

        /* Copy arguments and ensure return probe has no C argument */
        pev->nargs = argc - 1;
        pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs);
        if (pev->args == NULL) {
                ret = -ENOMEM;
                goto out;
        }
        for (i = 0; i < pev->nargs && ret >= 0; i++) {
                ret = parse_perf_probe_arg(argv[i + 1], &pev->args[i]);
                if (ret >= 0 &&
                    is_c_varname(pev->args[i].var) && pev->point.retprobe) {
                        semantic_error("You can't specify local variable for"
                                       " kretprobe.\n");
                        ret = -EINVAL;
                }
        }
out:
        argv_free(argv);

        return ret;
}

/* Return true if this perf_probe_event requires debuginfo */
bool perf_probe_event_need_dwarf(struct perf_probe_event *pev)
{
        int i;

        if (pev->point.file || pev->point.line || pev->point.lazy_line)
                return true;

        for (i = 0; i < pev->nargs; i++)
                if (is_c_varname(pev->args[i].var))
                        return true;

        return false;
}

/* Parse probe_events event into struct probe_point */
static int parse_probe_trace_command(const char *cmd,
                                     struct probe_trace_event *tev)
{
        struct probe_trace_point *tp = &tev->point;
        char pr;
        char *p;
        char *argv0_str = NULL, *fmt, *fmt1_str, *fmt2_str, *fmt3_str;
        int ret, i, argc;
        char **argv;

        pr_debug("Parsing probe_events: %s\n", cmd);
        argv = argv_split(cmd, &argc);
        if (!argv) {
                pr_debug("Failed to split arguments.\n");
                return -ENOMEM;
        }
        if (argc < 2) {
                semantic_error("Too few probe arguments.\n");
                ret = -ERANGE;
                goto out;
        }

        /* Scan event and group name. */
        argv0_str = strdup(argv[0]);
        if (argv0_str == NULL) {
                ret = -ENOMEM;
                goto out;
        }
        fmt1_str = strtok_r(argv0_str, ":", &fmt);
        fmt2_str = strtok_r(NULL, "/", &fmt);
        fmt3_str = strtok_r(NULL, " \t", &fmt);
        if (fmt1_str == NULL || strlen(fmt1_str) != 1 || fmt2_str == NULL
            || fmt3_str == NULL) {
                semantic_error("Failed to parse event name: %s\n", argv[0]);
                ret = -EINVAL;
                goto out;
        }
        pr = fmt1_str[0];
        tev->group = strdup(fmt2_str);
        tev->event = strdup(fmt3_str);
        if (tev->group == NULL || tev->event == NULL) {
                ret = -ENOMEM;
                goto out;
        }
        pr_debug("Group:%s Event:%s probe:%c\n", tev->group, tev->event, pr);

        tp->retprobe = (pr == 'r');

        /* Scan module name(if there), function name and offset */
        p = strchr(argv[1], ':');
        if (p) {
                tp->module = strndup(argv[1], p - argv[1]);
                p++;
        } else
                p = argv[1];
        fmt1_str = strtok_r(p, "+", &fmt);
        tp->symbol = strdup(fmt1_str);
        if (tp->symbol == NULL) {
                ret = -ENOMEM;
                goto out;
        }
        fmt2_str = strtok_r(NULL, "", &fmt);
        if (fmt2_str == NULL)
                tp->offset = 0;
        else
                tp->offset = strtoul(fmt2_str, NULL, 10);

        tev->nargs = argc - 2;
        tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
        if (tev->args == NULL) {
                ret = -ENOMEM;
                goto out;
        }
        for (i = 0; i < tev->nargs; i++) {
                p = strchr(argv[i + 2], '=');
                if (p)  /* We don't need which register is assigned. */
                        *p++ = '\0';
                else
                        p = argv[i + 2];
                tev->args[i].name = strdup(argv[i + 2]);
                /* TODO: parse regs and offset */
                tev->args[i].value = strdup(p);
                if (tev->args[i].name == NULL || tev->args[i].value == NULL) {
                        ret = -ENOMEM;
                        goto out;
                }
        }
        ret = 0;
out:
        free(argv0_str);
        argv_free(argv);
        return ret;
}

/* Compose only probe arg */
int synthesize_perf_probe_arg(struct perf_probe_arg *pa, char *buf, size_t len)
{
        struct perf_probe_arg_field *field = pa->field;
        int ret;
        char *tmp = buf;

        if (pa->name && pa->var)
                ret = e_snprintf(tmp, len, "%s=%s", pa->name, pa->var);
        else
                ret = e_snprintf(tmp, len, "%s", pa->name ? pa->name : pa->var);
        if (ret <= 0)
                goto error;
        tmp += ret;
        len -= ret;

        while (field) {
                if (field->name[0] == '[')
                        ret = e_snprintf(tmp, len, "%s", field->name);
                else
                        ret = e_snprintf(tmp, len, "%s%s",
                                         field->ref ? "->" : ".", field->name);
                if (ret <= 0)
                        goto error;
                tmp += ret;
                len -= ret;
                field = field->next;
        }

        if (pa->type) {
                ret = e_snprintf(tmp, len, ":%s", pa->type);
                if (ret <= 0)
                        goto error;
                tmp += ret;
                len -= ret;
        }

        return tmp - buf;
error:
        pr_debug("Failed to synthesize perf probe argument: %s\n",
                 strerror(-ret));
        return ret;
}

/* Compose only probe point (not argument) */
static char *synthesize_perf_probe_point(struct perf_probe_point *pp)
{
        char *buf, *tmp;
        char offs[32] = "", line[32] = "", file[32] = "";
        int ret, len;

        buf = zalloc(MAX_CMDLEN);
        if (buf == NULL) {
                ret = -ENOMEM;
                goto error;
        }
        if (pp->offset) {
                ret = e_snprintf(offs, 32, "+%lu", pp->offset);
                if (ret <= 0)
                        goto error;
        }
        if (pp->line) {
                ret = e_snprintf(line, 32, ":%d", pp->line);
                if (ret <= 0)
                        goto error;
        }
        if (pp->file) {
                tmp = pp->file;
                len = strlen(tmp);
                if (len > 30) {
                        tmp = strchr(pp->file + len - 30, '/');
                        tmp = tmp ? tmp + 1 : pp->file + len - 30;
                }
                ret = e_snprintf(file, 32, "@%s", tmp);
                if (ret <= 0)
                        goto error;
        }

        if (pp->function)
                ret = e_snprintf(buf, MAX_CMDLEN, "%s%s%s%s%s", pp->function,
                                 offs, pp->retprobe ? "%return" : "", line,
                                 file);
        else
                ret = e_snprintf(buf, MAX_CMDLEN, "%s%s", file, line);
        if (ret <= 0)
                goto error;

        return buf;
error:
        pr_debug("Failed to synthesize perf probe point: %s\n",
                 strerror(-ret));
        if (buf)
                free(buf);
        return NULL;
}

#if 0
char *synthesize_perf_probe_command(struct perf_probe_event *pev)
{
        char *buf;
        int i, len, ret;

        buf = synthesize_perf_probe_point(&pev->point);
        if (!buf)
                return NULL;

        len = strlen(buf);
        for (i = 0; i < pev->nargs; i++) {
                ret = e_snprintf(&buf[len], MAX_CMDLEN - len, " %s",
                                 pev->args[i].name);
                if (ret <= 0) {
                        free(buf);
                        return NULL;
                }
                len += ret;
        }

        return buf;
}
#endif

static int __synthesize_probe_trace_arg_ref(struct probe_trace_arg_ref *ref,
                                             char **buf, size_t *buflen,
                                             int depth)
{
        int ret;
        if (ref->next) {
                depth = __synthesize_probe_trace_arg_ref(ref->next, buf,
                                                         buflen, depth + 1);
                if (depth < 0)
                        goto out;
        }

        ret = e_snprintf(*buf, *buflen, "%+ld(", ref->offset);
        if (ret < 0)
                depth = ret;
        else {
                *buf += ret;
                *buflen -= ret;
        }
out:
        return depth;

}

static int synthesize_probe_trace_arg(struct probe_trace_arg *arg,
                                       char *buf, size_t buflen)
{
        struct probe_trace_arg_ref *ref = arg->ref;
        int ret, depth = 0;
        char *tmp = buf;

        /* Argument name or separator */
        if (arg->name)
                ret = e_snprintf(buf, buflen, " %s=", arg->name);
        else
                ret = e_snprintf(buf, buflen, " ");
        if (ret < 0)
                return ret;
        buf += ret;
        buflen -= ret;

        /* Special case: @XXX */
        if (arg->value[0] == '@' && arg->ref)
                        ref = ref->next;

        /* Dereferencing arguments */
        if (ref) {
                depth = __synthesize_probe_trace_arg_ref(ref, &buf,
                                                          &buflen, 1);
                if (depth < 0)
                        return depth;
        }

        /* Print argument value */
        if (arg->value[0] == '@' && arg->ref)
                ret = e_snprintf(buf, buflen, "%s%+ld", arg->value,
                                 arg->ref->offset);
        else
                ret = e_snprintf(buf, buflen, "%s", arg->value);
        if (ret < 0)
                return ret;
        buf += ret;
        buflen -= ret;

        /* Closing */
        while (depth--) {
                ret = e_snprintf(buf, buflen, ")");
                if (ret < 0)
                        return ret;
                buf += ret;
                buflen -= ret;
        }
        /* Print argument type */
        if (arg->type) {
                ret = e_snprintf(buf, buflen, ":%s", arg->type);
                if (ret <= 0)
                        return ret;
                buf += ret;
        }

        return buf - tmp;
}

char *synthesize_probe_trace_command(struct probe_trace_event *tev)
{
        struct probe_trace_point *tp = &tev->point;
        char *buf;
        int i, len, ret;

        buf = zalloc(MAX_CMDLEN);
        if (buf == NULL)
                return NULL;

        if (tev->uprobes)
                len = e_snprintf(buf, MAX_CMDLEN, "%c:%s/%s %s:%s",
                                 tp->retprobe ? 'r' : 'p',
                                 tev->group, tev->event,
                                 tp->module, tp->symbol);
        else
                len = e_snprintf(buf, MAX_CMDLEN, "%c:%s/%s %s%s%s+%lu",
                                 tp->retprobe ? 'r' : 'p',
                                 tev->group, tev->event,
                                 tp->module ?: "", tp->module ? ":" : "",
                                 tp->symbol, tp->offset);

        if (len <= 0)
                goto error;

        for (i = 0; i < tev->nargs; i++) {
                ret = synthesize_probe_trace_arg(&tev->args[i], buf + len,
                                                  MAX_CMDLEN - len);
                if (ret <= 0)
                        goto error;
                len += ret;
        }

        return buf;
error:
        free(buf);
        return NULL;
}

static int convert_to_perf_probe_event(struct probe_trace_event *tev,
                               struct perf_probe_event *pev, bool is_kprobe)
{
        char buf[64] = "";
        int i, ret;

        /* Convert event/group name */
        pev->event = strdup(tev->event);
        pev->group = strdup(tev->group);
        if (pev->event == NULL || pev->group == NULL)
                return -ENOMEM;

        /* Convert trace_point to probe_point */
        if (is_kprobe)
                ret = kprobe_convert_to_perf_probe(&tev->point, &pev->point);
        else
                ret = convert_to_perf_probe_point(&tev->point, &pev->point);

        if (ret < 0)
                return ret;

        /* Convert trace_arg to probe_arg */
        pev->nargs = tev->nargs;
        pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs);
        if (pev->args == NULL)
                return -ENOMEM;
        for (i = 0; i < tev->nargs && ret >= 0; i++) {
                if (tev->args[i].name)
                        pev->args[i].name = strdup(tev->args[i].name);
                else {
                        ret = synthesize_probe_trace_arg(&tev->args[i],
                                                          buf, 64);
                        pev->args[i].name = strdup(buf);
                }
                if (pev->args[i].name == NULL && ret >= 0)
                        ret = -ENOMEM;
        }

        if (ret < 0)
                clear_perf_probe_event(pev);

        return ret;
}

void clear_perf_probe_event(struct perf_probe_event *pev)
{
        struct perf_probe_point *pp = &pev->point;
        struct perf_probe_arg_field *field, *next;
        int i;

        if (pev->event)
                free(pev->event);
        if (pev->group)
                free(pev->group);
        if (pp->file)
                free(pp->file);
        if (pp->function)
                free(pp->function);
        if (pp->lazy_line)
                free(pp->lazy_line);
        for (i = 0; i < pev->nargs; i++) {
                if (pev->args[i].name)
                        free(pev->args[i].name);
                if (pev->args[i].var)
                        free(pev->args[i].var);
                if (pev->args[i].type)
                        free(pev->args[i].type);
                field = pev->args[i].field;
                while (field) {
                        next = field->next;
                        if (field->name)
                                free(field->name);
                        free(field);
                        field = next;
                }
        }
        if (pev->args)
                free(pev->args);
        memset(pev, 0, sizeof(*pev));
}

static void clear_probe_trace_event(struct probe_trace_event *tev)
{
        struct probe_trace_arg_ref *ref, *next;
        int i;

        if (tev->event)
                free(tev->event);
        if (tev->group)
                free(tev->group);
        if (tev->point.symbol)
                free(tev->point.symbol);
        if (tev->point.module)
                free(tev->point.module);
        for (i = 0; i < tev->nargs; i++) {
                if (tev->args[i].name)
                        free(tev->args[i].name);
                if (tev->args[i].value)
                        free(tev->args[i].value);
                if (tev->args[i].type)
                        free(tev->args[i].type);
                ref = tev->args[i].ref;
                while (ref) {
                        next = ref->next;
                        free(ref);
                        ref = next;
                }
        }
        if (tev->args)
                free(tev->args);
        memset(tev, 0, sizeof(*tev));
}

static void print_warn_msg(const char *file, bool is_kprobe)
{

        if (errno == ENOENT) {
                const char *config;

                if (!is_kprobe)
                        config = "CONFIG_UPROBE_EVENTS";
                else
                        config = "CONFIG_KPROBE_EVENTS";

                pr_warning("%s file does not exist - please rebuild kernel"
                                " with %s.\n", file, config);
        } else
                pr_warning("Failed to open %s file: %s\n", file,
                                strerror(errno));
}

static int open_probe_events(const char *trace_file, bool readwrite,
                                bool is_kprobe)
{
        char buf[PATH_MAX];
        const char *__debugfs;
        int ret;

        __debugfs = debugfs_find_mountpoint();
        if (__debugfs == NULL) {
                pr_warning("Debugfs is not mounted.\n");
                return -ENOENT;
        }

        ret = e_snprintf(buf, PATH_MAX, "%s/%s", __debugfs, trace_file);
        if (ret >= 0) {
                pr_debug("Opening %s write=%d\n", buf, readwrite);
                if (readwrite && !probe_event_dry_run)
                        ret = open(buf, O_RDWR, O_APPEND);
                else
                        ret = open(buf, O_RDONLY, 0);

                if (ret < 0)
                        print_warn_msg(buf, is_kprobe);
        }
        return ret;
}

static int open_kprobe_events(bool readwrite)
{
        return open_probe_events("tracing/kprobe_events", readwrite, true);
}

static int open_uprobe_events(bool readwrite)
{
        return open_probe_events("tracing/uprobe_events", readwrite, false);
}

/* Get raw string list of current kprobe_events  or uprobe_events */
static struct strlist *get_probe_trace_command_rawlist(int fd)
{
        int ret, idx;
        FILE *fp;
        char buf[MAX_CMDLEN];
        char *p;
        struct strlist *sl;

        sl = strlist__new(true, NULL);

        fp = fdopen(dup(fd), "r");
        while (!feof(fp)) {
                p = fgets(buf, MAX_CMDLEN, fp);
                if (!p)
                        break;

                idx = strlen(p) - 1;
                if (p[idx] == '\n')
                        p[idx] = '\0';
                ret = strlist__add(sl, buf);
                if (ret < 0) {
                        pr_debug("strlist__add failed: %s\n", strerror(-ret));
                        strlist__delete(sl);
                        return NULL;
                }
        }
        fclose(fp);

        return sl;
}

/* Show an event */
static int show_perf_probe_event(struct perf_probe_event *pev)
{
        int i, ret;
        char buf[128];
        char *place;

        /* Synthesize only event probe point */
        place = synthesize_perf_probe_point(&pev->point);
        if (!place)
                return -EINVAL;

        ret = e_snprintf(buf, 128, "%s:%s", pev->group, pev->event);
        if (ret < 0)
                return ret;

        printf("  %-20s (on %s", buf, place);

        if (pev->nargs > 0) {
                printf(" with");
                for (i = 0; i < pev->nargs; i++) {
                        ret = synthesize_perf_probe_arg(&pev->args[i],
                                                        buf, 128);
                        if (ret < 0)
                                break;
                        printf(" %s", buf);
                }
        }
        printf(")\n");
        free(place);
        return ret;
}

static int __show_perf_probe_events(int fd, bool is_kprobe)
{
        int ret = 0;
        struct probe_trace_event tev;
        struct perf_probe_event pev;
        struct strlist *rawlist;
        struct str_node *ent;

        memset(&tev, 0, sizeof(tev));
        memset(&pev, 0, sizeof(pev));

        rawlist = get_probe_trace_command_rawlist(fd);
        if (!rawlist)
                return -ENOENT;

        strlist__for_each(ent, rawlist) {
                ret = parse_probe_trace_command(ent->s, &tev);
                if (ret >= 0) {
                        ret = convert_to_perf_probe_event(&tev, &pev,
                                                                is_kprobe);
                        if (ret >= 0)
                                ret = show_perf_probe_event(&pev);
                }
                clear_perf_probe_event(&pev);
                clear_probe_trace_event(&tev);
                if (ret < 0)
                        break;
        }
        strlist__delete(rawlist);

        return ret;
}

/* List up current perf-probe events */
int show_perf_probe_events(void)
{
        int fd, ret;

        setup_pager();
        fd = open_kprobe_events(false);

        if (fd < 0)
                return fd;

        ret = init_vmlinux();
        if (ret < 0)
                return ret;

        ret = __show_perf_probe_events(fd, true);
        close(fd);

        fd = open_uprobe_events(false);
        if (fd >= 0) {
                ret = __show_perf_probe_events(fd, false);
                close(fd);
        }

        return ret;
}

/* Get current perf-probe event names */
static struct strlist *get_probe_trace_event_names(int fd, bool include_group)
{
        char buf[128];
        struct strlist *sl, *rawlist;
        struct str_node *ent;
        struct probe_trace_event tev;
        int ret = 0;

        memset(&tev, 0, sizeof(tev));
        rawlist = get_probe_trace_command_rawlist(fd);
        sl = strlist__new(true, NULL);
        strlist__for_each(ent, rawlist) {
                ret = parse_probe_trace_command(ent->s, &tev);
                if (ret < 0)
                        break;
                if (include_group) {
                        ret = e_snprintf(buf, 128, "%s:%s", tev.group,
                                        tev.event);
                        if (ret >= 0)
                                ret = strlist__add(sl, buf);
                } else
                        ret = strlist__add(sl, tev.event);
                clear_probe_trace_event(&tev);
                if (ret < 0)
                        break;
        }
        strlist__delete(rawlist);

        if (ret < 0) {
                strlist__delete(sl);
                return NULL;
        }
        return sl;
}

static int write_probe_trace_event(int fd, struct probe_trace_event *tev)
{
        int ret = 0;
        char *buf = synthesize_probe_trace_command(tev);

        if (!buf) {
                pr_debug("Failed to synthesize probe trace event.\n");
                return -EINVAL;
        }

        pr_debug("Writing event: %s\n", buf);
        if (!probe_event_dry_run) {
                ret = write(fd, buf, strlen(buf));
                if (ret <= 0)
                        pr_warning("Failed to write event: %s\n",
                                   strerror(errno));
        }
        free(buf);
        return ret;
}

static int get_new_event_name(char *buf, size_t len, const char *base,
                              struct strlist *namelist, bool allow_suffix)
{
        int i, ret;

        /* Try no suffix */
        ret = e_snprintf(buf, len, "%s", base);
        if (ret < 0) {
                pr_debug("snprintf() failed: %s\n", strerror(-ret));
                return ret;
        }
        if (!strlist__has_entry(namelist, buf))
                return 0;

        if (!allow_suffix) {
                pr_warning("Error: event \"%s\" already exists. "
                           "(Use -f to force duplicates.)\n", base);
                return -EEXIST;
        }

        /* Try to add suffix */
        for (i = 1; i < MAX_EVENT_INDEX; i++) {
                ret = e_snprintf(buf, len, "%s_%d", base, i);
                if (ret < 0) {
                        pr_debug("snprintf() failed: %s\n", strerror(-ret));
                        return ret;
                }
                if (!strlist__has_entry(namelist, buf))
                        break;
        }
        if (i == MAX_EVENT_INDEX) {
                pr_warning("Too many events are on the same function.\n");
                ret = -ERANGE;
        }

        return ret;
}

static int __add_probe_trace_events(struct perf_probe_event *pev,
                                     struct probe_trace_event *tevs,
                                     int ntevs, bool allow_suffix)
{
        int i, fd, ret;
        struct probe_trace_event *tev = NULL;
        char buf[64];
        const char *event, *group;
        struct strlist *namelist;

        if (pev->uprobes)
                fd = open_uprobe_events(true);
        else
                fd = open_kprobe_events(true);

        if (fd < 0)
                return fd;
        /* Get current event names */
        namelist = get_probe_trace_event_names(fd, false);
        if (!namelist) {
                pr_debug("Failed to get current event list.\n");
                return -EIO;
        }

        ret = 0;
        printf("Added new event%s\n", (ntevs > 1) ? "s:" : ":");
        for (i = 0; i < ntevs; i++) {
                tev = &tevs[i];
                if (pev->event)
                        event = pev->event;
                else
                        if (pev->point.function)
                                event = pev->point.function;
                        else
                                event = tev->point.symbol;
                if (pev->group)
                        group = pev->group;
                else
                        group = PERFPROBE_GROUP;

                /* Get an unused new event name */
                ret = get_new_event_name(buf, 64, event,
                                         namelist, allow_suffix);
                if (ret < 0)
                        break;
                event = buf;

                tev->event = strdup(event);
                tev->group = strdup(group);
                if (tev->event == NULL || tev->group == NULL) {
                        ret = -ENOMEM;
                        break;
                }
                ret = write_probe_trace_event(fd, tev);
                if (ret < 0)
                        break;
                /* Add added event name to namelist */
                strlist__add(namelist, event);

                /* Trick here - save current event/group */
                event = pev->event;
                group = pev->group;
                pev->event = tev->event;
                pev->group = tev->group;
                show_perf_probe_event(pev);
                /* Trick here - restore current event/group */
                pev->event = (char *)event;
                pev->group = (char *)group;

                /*
                 * Probes after the first probe which comes from same
                 * user input are always allowed to add suffix, because
                 * there might be several addresses corresponding to
                 * one code line.
                 */
                allow_suffix = true;
        }

        if (ret >= 0) {
                /* Show how to use the event. */
                printf("\nYou can now use it in all perf tools, such as:\n\n");
                printf("\tperf record -e %s:%s -aR sleep 1\n\n", tev->group,
                         tev->event);
        }

        strlist__delete(namelist);
        close(fd);
        return ret;
}

static int convert_to_probe_trace_events(struct perf_probe_event *pev,
                                          struct probe_trace_event **tevs,
                                          int max_tevs, const char *target)
{
        struct symbol *sym;
        int ret = 0, i;
        struct probe_trace_event *tev;

        /* Convert perf_probe_event with debuginfo */
        ret = try_to_find_probe_trace_events(pev, tevs, max_tevs, target);
        if (ret != 0)
                return ret;     /* Found in debuginfo or got an error */

        /* Allocate trace event buffer */
        tev = *tevs = zalloc(sizeof(struct probe_trace_event));
        if (tev == NULL)
                return -ENOMEM;

        /* Copy parameters */
        tev->point.symbol = strdup(pev->point.function);
        if (tev->point.symbol == NULL) {
                ret = -ENOMEM;
                goto error;
        }

        if (target) {
                tev->point.module = strdup(target);
                if (tev->point.module == NULL) {
                        ret = -ENOMEM;
                        goto error;
                }
        }

        tev->point.offset = pev->point.offset;
        tev->point.retprobe = pev->point.retprobe;
        tev->nargs = pev->nargs;
        tev->uprobes = pev->uprobes;

        if (tev->nargs) {
                tev->args = zalloc(sizeof(struct probe_trace_arg)
                                   * tev->nargs);
                if (tev->args == NULL) {
                        ret = -ENOMEM;
                        goto error;
                }
                for (i = 0; i < tev->nargs; i++) {
                        if (pev->args[i].name) {
                                tev->args[i].name = strdup(pev->args[i].name);
                                if (tev->args[i].name == NULL) {
                                        ret = -ENOMEM;
                                        goto error;
                                }
                        }
                        tev->args[i].value = strdup(pev->args[i].var);
                        if (tev->args[i].value == NULL) {
                                ret = -ENOMEM;
                                goto error;
                        }
                        if (pev->args[i].type) {
                                tev->args[i].type = strdup(pev->args[i].type);
                                if (tev->args[i].type == NULL) {
                                        ret = -ENOMEM;
                                        goto error;
                                }
                        }
                }
        }

        if (pev->uprobes)
                return 1;

        /* Currently just checking function name from symbol map */
        sym = __find_kernel_function_by_name(tev->point.symbol, NULL);
        if (!sym) {
                pr_warning("Kernel symbol \'%s\' not found.\n",
                           tev->point.symbol);
                ret = -ENOENT;
                goto error;
        } else if (tev->point.offset > sym->end - sym->start) {
                pr_warning("Offset specified is greater than size of %s\n",
                           tev->point.symbol);
                ret = -ENOENT;
                goto error;

        }

        return 1;
error:
        clear_probe_trace_event(tev);
        free(tev);
        *tevs = NULL;
        return ret;
}

struct __event_package {
        struct perf_probe_event         *pev;
        struct probe_trace_event        *tevs;
        int                             ntevs;
};

int add_perf_probe_events(struct perf_probe_event *pevs, int npevs,
                          int max_tevs, const char *target, bool force_add)
{
        int i, j, ret;
        struct __event_package *pkgs;

        ret = 0;
        pkgs = zalloc(sizeof(struct __event_package) * npevs);

        if (pkgs == NULL)
                return -ENOMEM;

        if (!pevs->uprobes)
                /* Init vmlinux path */
                ret = init_vmlinux();
        else
                ret = init_user_exec();

        if (ret < 0) {
                free(pkgs);
                return ret;
        }

        /* Loop 1: convert all events */
        for (i = 0; i < npevs; i++) {
                pkgs[i].pev = &pevs[i];
                /* Convert with or without debuginfo */
                ret  = convert_to_probe_trace_events(pkgs[i].pev,
                                                     &pkgs[i].tevs,
                                                     max_tevs,
                                                     target);
                if (ret < 0)
                        goto end;
                pkgs[i].ntevs = ret;
        }

        /* Loop 2: add all events */
        for (i = 0; i < npevs; i++) {
                ret = __add_probe_trace_events(pkgs[i].pev, pkgs[i].tevs,
                                                pkgs[i].ntevs, force_add);
                if (ret < 0)
                        break;
        }
end:
        /* Loop 3: cleanup and free trace events  */
        for (i = 0; i < npevs; i++) {
                for (j = 0; j < pkgs[i].ntevs; j++)
                        clear_probe_trace_event(&pkgs[i].tevs[j]);
                free(pkgs[i].tevs);
        }
        free(pkgs);

        return ret;
}

static int __del_trace_probe_event(int fd, struct str_node *ent)
{
        char *p;
        char buf[128];
        int ret;

        /* Convert from perf-probe event to trace-probe event */
        ret = e_snprintf(buf, 128, "-:%s", ent->s);
        if (ret < 0)
                goto error;

        p = strchr(buf + 2, ':');
        if (!p) {
                pr_debug("Internal error: %s should have ':' but not.\n",
                         ent->s);
                ret = -ENOTSUP;
                goto error;
        }
        *p = '/';

        pr_debug("Writing event: %s\n", buf);
        ret = write(fd, buf, strlen(buf));
        if (ret < 0) {
                ret = -errno;
                goto error;
        }

        printf("Removed event: %s\n", ent->s);
        return 0;
error:
        pr_warning("Failed to delete event: %s\n", strerror(-ret));
        return ret;
}

static int del_trace_probe_event(int fd, const char *buf,
                                                  struct strlist *namelist)
{
        struct str_node *ent, *n;
        int ret = -1;

        if (strpbrk(buf, "*?")) { /* Glob-exp */
                strlist__for_each_safe(ent, n, namelist)
                        if (strglobmatch(ent->s, buf)) {
                                ret = __del_trace_probe_event(fd, ent);
                                if (ret < 0)
                                        break;
                                strlist__remove(namelist, ent);
                        }
        } else {
                ent = strlist__find(namelist, buf);
                if (ent) {
                        ret = __del_trace_probe_event(fd, ent);
                        if (ret >= 0)
                                strlist__remove(namelist, ent);
                }
        }

        return ret;
}

int del_perf_probe_events(struct strlist *dellist)
{
        int ret = -1, ufd = -1, kfd = -1;
        char buf[128];
        const char *group, *event;
        char *p, *str;
        struct str_node *ent;
        struct strlist *namelist = NULL, *unamelist = NULL;

        /* Get current event names */
        kfd = open_kprobe_events(true);
        if (kfd < 0)
                return kfd;

        namelist = get_probe_trace_event_names(kfd, true);
        ufd = open_uprobe_events(true);

        if (ufd >= 0)
                unamelist = get_probe_trace_event_names(ufd, true);

        if (namelist == NULL && unamelist == NULL)
                goto error;

        strlist__for_each(ent, dellist) {
                str = strdup(ent->s);
                if (str == NULL) {
                        ret = -ENOMEM;
                        goto error;
                }
                pr_debug("Parsing: %s\n", str);
                p = strchr(str, ':');
                if (p) {
                        group = str;
                        *p = '\0';
                        event = p + 1;
                } else {
                        group = "*";
                        event = str;
                }

                ret = e_snprintf(buf, 128, "%s:%s", group, event);
                if (ret < 0) {
                        pr_err("Failed to copy event.");
                        free(str);
                        goto error;
                }

                pr_debug("Group: %s, Event: %s\n", group, event);

                if (namelist)
                        ret = del_trace_probe_event(kfd, buf, namelist);

                if (unamelist && ret != 0)
                        ret = del_trace_probe_event(ufd, buf, unamelist);

                if (ret != 0)
                        pr_info("Info: Event \"%s\" does not exist.\n", buf);

                free(str);
        }

error:
        if (kfd >= 0) {
                strlist__delete(namelist);
                close(kfd);
        }

        if (ufd >= 0) {
                strlist__delete(unamelist);
                close(ufd);
        }

        return ret;
}

/* TODO: don't use a global variable for filter ... */
static struct strfilter *available_func_filter;

/*
 * If a symbol corresponds to a function with global binding and
 * matches filter return 0. For all others return 1.
 */
static int filter_available_functions(struct map *map __maybe_unused,
                                      struct symbol *sym)
{
        if (sym->binding == STB_GLOBAL &&
            strfilter__compare(available_func_filter, sym->name))
                return 0;
        return 1;
}

static int __show_available_funcs(struct map *map)
{
        if (map__load(map, filter_available_functions)) {
                pr_err("Failed to load map.\n");
                return -EINVAL;
        }
        if (!dso__sorted_by_name(map->dso, map->type))
                dso__sort_by_name(map->dso, map->type);

        dso__fprintf_symbols_by_name(map->dso, map->type, stdout);
        return 0;
}

static int available_kernel_funcs(const char *module)
{
        struct map *map;
        int ret;

        ret = init_vmlinux();
        if (ret < 0)
                return ret;

        map = kernel_get_module_map(module);
        if (!map) {
                pr_err("Failed to find %s map.\n", (module) ? : "kernel");
                return -EINVAL;
        }
        return __show_available_funcs(map);
}

static int available_user_funcs(const char *target)
{
        struct map *map;
        int ret;

        ret = init_user_exec();
        if (ret < 0)
                return ret;

        map = dso__new_map(target);
        ret = __show_available_funcs(map);
        dso__delete(map->dso);
        map__delete(map);
        return ret;
}

int show_available_funcs(const char *target, struct strfilter *_filter,
                                        bool user)
{
        setup_pager();
        available_func_filter = _filter;

        if (!user)
                return available_kernel_funcs(target);

        return available_user_funcs(target);
}

/*
 * uprobe_events only accepts address:
 * Convert function and any offset to address
 */
static int convert_name_to_addr(struct perf_probe_event *pev, const char *exec)
{
        struct perf_probe_point *pp = &pev->point;
        struct symbol *sym;
        struct map *map = NULL;
        char *function = NULL, *name = NULL;
        int ret = -EINVAL;
        unsigned long long vaddr = 0;

        if (!pp->function) {
                pr_warning("No function specified for uprobes");
                goto out;
        }

        function = strdup(pp->function);
        if (!function) {
                pr_warning("Failed to allocate memory by strdup.\n");
                ret = -ENOMEM;
                goto out;
        }

        name = realpath(exec, NULL);
        if (!name) {
                pr_warning("Cannot find realpath for %s.\n", exec);
                goto out;
        }
        map = dso__new_map(name);
        if (!map) {
                pr_warning("Cannot find appropriate DSO for %s.\n", exec);
                goto out;
        }
        available_func_filter = strfilter__new(function, NULL);
        if (map__load(map, filter_available_functions)) {
                pr_err("Failed to load map.\n");
                goto out;
        }

        sym = map__find_symbol_by_name(map, function, NULL);
        if (!sym) {
                pr_warning("Cannot find %s in DSO %s\n", function, exec);
                goto out;
        }

        if (map->start > sym->start)
                vaddr = map->start;
        vaddr += sym->start + pp->offset + map->pgoff;
        pp->offset = 0;

        if (!pev->event) {
                pev->event = function;
                function = NULL;
        }
        if (!pev->group) {
                char *ptr1, *ptr2, *exec_copy;

                pev->group = zalloc(sizeof(char *) * 64);
                exec_copy = strdup(exec);
                if (!exec_copy) {
                        ret = -ENOMEM;
                        pr_warning("Failed to copy exec string.\n");
                        goto out;
                }

                ptr1 = strdup(basename(exec_copy));
                if (ptr1) {
                        ptr2 = strpbrk(ptr1, "-._");
                        if (ptr2)
                                *ptr2 = '\0';
                        e_snprintf(pev->group, 64, "%s_%s", PERFPROBE_GROUP,
                                        ptr1);
                        free(ptr1);
                }
                free(exec_copy);
        }
        free(pp->function);
        pp->function = zalloc(sizeof(char *) * MAX_PROBE_ARGS);
        if (!pp->function) {
                ret = -ENOMEM;
                pr_warning("Failed to allocate memory by zalloc.\n");
                goto out;
        }
        e_snprintf(pp->function, MAX_PROBE_ARGS, "0x%llx", vaddr);
        ret = 0;

out:
        if (map) {
                dso__delete(map->dso);
                map__delete(map);
        }
        if (function)
                free(function);
        if (name)
                free(name);
        return ret;
}