[mirror_ubuntu-disco-kernel.git] / tools / perf / util / util.c

// SPDX-License-Identifier: GPL-2.0
#include "../perf.h"
#include "util.h"
#include "debug.h"
#include <api/fs/fs.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/utsname.h>
#include <dirent.h>
#include <inttypes.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <limits.h>
#include <linux/kernel.h>
#include <linux/log2.h>
#include <linux/time64.h>
#include <unistd.h>
#include "strlist.h"

/*
 * XXX We need to find a better place for these things...
 */
unsigned int page_size;
int cacheline_size;

int sysctl_perf_event_max_stack = PERF_MAX_STACK_DEPTH;
int sysctl_perf_event_max_contexts_per_stack = PERF_MAX_CONTEXTS_PER_STACK;

bool test_attr__enabled;

bool perf_host  = true;
bool perf_guest = false;

void event_attr_init(struct perf_event_attr *attr)
{
	if (!perf_host)
		attr->exclude_host  = 1;
	if (!perf_guest)
		attr->exclude_guest = 1;
	/* to capture ABI version */
	attr->size = sizeof(*attr);
}

int mkdir_p(char *path, mode_t mode)
{
	struct stat st;
	int err;
	char *d = path;

	if (*d != '/')
		return -1;

	if (stat(path, &st) == 0)
		return 0;

	while (*++d == '/');

	while ((d = strchr(d, '/'))) {
		*d = '\0';
		err = stat(path, &st) && mkdir(path, mode);
		*d++ = '/';
		if (err)
			return -1;
		while (*d == '/')
			++d;
	}
	return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
}

int rm_rf(const char *path)
{
	DIR *dir;
	int ret = 0;
	struct dirent *d;
	char namebuf[PATH_MAX];

	dir = opendir(path);
	if (dir == NULL)
		return 0;

	while ((d = readdir(dir)) != NULL && !ret) {
		struct stat statbuf;

		if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
			continue;

		scnprintf(namebuf, sizeof(namebuf), "%s/%s",
			  path, d->d_name);

		/* We have to check symbolic link itself */
		ret = lstat(namebuf, &statbuf);
		if (ret < 0) {
			pr_debug("stat failed: %s\n", namebuf);
			break;
		}

		if (S_ISDIR(statbuf.st_mode))
			ret = rm_rf(namebuf);
		else
			ret = unlink(namebuf);
	}
	closedir(dir);

	if (ret < 0)
		return ret;

	return rmdir(path);
}

/* A filter which removes dot files */
bool lsdir_no_dot_filter(const char *name __maybe_unused, struct dirent *d)
{
	return d->d_name[0] != '.';
}

/* lsdir reads a directory and store it in strlist */
struct strlist *lsdir(const char *name,
		      bool (*filter)(const char *, struct dirent *))
{
	struct strlist *list = NULL;
	DIR *dir;
	struct dirent *d;

	dir = opendir(name);
	if (!dir)
		return NULL;

	list = strlist__new(NULL, NULL);
	if (!list) {
		errno = ENOMEM;
		goto out;
	}

	while ((d = readdir(dir)) != NULL) {
		if (!filter || filter(name, d))
			strlist__add(list, d->d_name);
	}

out:
	closedir(dir);
	return list;
}

static int slow_copyfile(const char *from, const char *to, struct nsinfo *nsi)
{
	int err = -1;
	char *line = NULL;
	size_t n;
	FILE *from_fp, *to_fp;
	struct nscookie nsc;

	nsinfo__mountns_enter(nsi, &nsc);
	from_fp = fopen(from, "r");
	nsinfo__mountns_exit(&nsc);
	if (from_fp == NULL)
		goto out;

	to_fp = fopen(to, "w");
	if (to_fp == NULL)
		goto out_fclose_from;

	while (getline(&line, &n, from_fp) > 0)
		if (fputs(line, to_fp) == EOF)
			goto out_fclose_to;
	err = 0;
out_fclose_to:
	fclose(to_fp);
	free(line);
out_fclose_from:
	fclose(from_fp);
out:
	return err;
}

int copyfile_offset(int ifd, loff_t off_in, int ofd, loff_t off_out, u64 size)
{
	void *ptr;
	loff_t pgoff;

	pgoff = off_in & ~(page_size - 1);
	off_in -= pgoff;

	ptr = mmap(NULL, off_in + size, PROT_READ, MAP_PRIVATE, ifd, pgoff);
	if (ptr == MAP_FAILED)
		return -1;

	while (size) {
		ssize_t ret = pwrite(ofd, ptr + off_in, size, off_out);
		if (ret < 0 && errno == EINTR)
			continue;
		if (ret <= 0)
			break;

		size -= ret;
		off_in += ret;
		off_out -= ret;
	}
	munmap(ptr, off_in + size);

	return size ? -1 : 0;
}

static int copyfile_mode_ns(const char *from, const char *to, mode_t mode,
			    struct nsinfo *nsi)
{
	int fromfd, tofd;
	struct stat st;
	int err;
	char *tmp = NULL, *ptr = NULL;
	struct nscookie nsc;

	nsinfo__mountns_enter(nsi, &nsc);
	err = stat(from, &st);
	nsinfo__mountns_exit(&nsc);
	if (err)
		goto out;
	err = -1;

	/* extra 'x' at the end is to reserve space for '.' */
	if (asprintf(&tmp, "%s.XXXXXXx", to) < 0) {
		tmp = NULL;
		goto out;
	}
	ptr = strrchr(tmp, '/');
	if (!ptr)
		goto out;
	ptr = memmove(ptr + 1, ptr, strlen(ptr) - 1);
	*ptr = '.';

	tofd = mkstemp(tmp);
	if (tofd < 0)
		goto out;

	if (fchmod(tofd, mode))
		goto out_close_to;

	if (st.st_size == 0) { /* /proc? do it slowly... */
		err = slow_copyfile(from, tmp, nsi);
		goto out_close_to;
	}

	nsinfo__mountns_enter(nsi, &nsc);
	fromfd = open(from, O_RDONLY);
	nsinfo__mountns_exit(&nsc);
	if (fromfd < 0)
		goto out_close_to;

	err = copyfile_offset(fromfd, 0, tofd, 0, st.st_size);

	close(fromfd);
out_close_to:
	close(tofd);
	if (!err)
		err = link(tmp, to);
	unlink(tmp);
out:
	free(tmp);
	return err;
}

int copyfile_ns(const char *from, const char *to, struct nsinfo *nsi)
{
	return copyfile_mode_ns(from, to, 0755, nsi);
}

int copyfile_mode(const char *from, const char *to, mode_t mode)
{
	return copyfile_mode_ns(from, to, mode, NULL);
}

int copyfile(const char *from, const char *to)
{
	return copyfile_mode(from, to, 0755);
}

static ssize_t ion(bool is_read, int fd, void *buf, size_t n)
{
	void *buf_start = buf;
	size_t left = n;

	while (left) {
		/* buf must be treated as const if !is_read. */
		ssize_t ret = is_read ? read(fd, buf, left) :
					write(fd, buf, left);

		if (ret < 0 && errno == EINTR)
			continue;
		if (ret <= 0)
			return ret;

		left -= ret;
		buf  += ret;
	}

	BUG_ON((size_t)(buf - buf_start) != n);
	return n;
}

/*
 * Read exactly 'n' bytes or return an error.
 */
ssize_t readn(int fd, void *buf, size_t n)
{
	return ion(true, fd, buf, n);
}

/*
 * Write exactly 'n' bytes or return an error.
 */
ssize_t writen(int fd, const void *buf, size_t n)
{
	/* ion does not modify buf. */
	return ion(false, fd, (void *)buf, n);
}

size_t hex_width(u64 v)
{
	size_t n = 1;

	while ((v >>= 4))
		++n;

	return n;
}

static int hex(char ch)
{
	if ((ch >= '0') && (ch <= '9'))
		return ch - '0';
	if ((ch >= 'a') && (ch <= 'f'))
		return ch - 'a' + 10;
	if ((ch >= 'A') && (ch <= 'F'))
		return ch - 'A' + 10;
	return -1;
}

/*
 * While we find nice hex chars, build a long_val.
 * Return number of chars processed.
 */
int hex2u64(const char *ptr, u64 *long_val)
{
	const char *p = ptr;
	*long_val = 0;

	while (*p) {
		const int hex_val = hex(*p);

		if (hex_val < 0)
			break;

		*long_val = (*long_val << 4) | hex_val;
		p++;
	}

	return p - ptr;
}

int perf_event_paranoid(void)
{
	int value;

	if (sysctl__read_int("kernel/perf_event_paranoid", &value))
		return INT_MAX;

	return value;
}
static int
fetch_ubuntu_kernel_version(unsigned int *puint)
{
	ssize_t len;
	size_t line_len = 0;
	char *ptr, *line = NULL;
	int version, patchlevel, sublevel, err;
	FILE *vsig;

	if (!puint)
		return 0;

	vsig = fopen("/proc/version_signature", "r");
	if (!vsig) {
		pr_debug("Open /proc/version_signature failed: %s\n",
			 strerror(errno));
		return -1;
	}

	len = getline(&line, &line_len, vsig);
	fclose(vsig);
	err = -1;
	if (len <= 0) {
		pr_debug("Reading from /proc/version_signature failed: %s\n",
			 strerror(errno));
		goto errout;
	}

	ptr = strrchr(line, ' ');
	if (!ptr) {
		pr_debug("Parsing /proc/version_signature failed: %s\n", line);
		goto errout;
	}

	err = sscanf(ptr + 1, "%d.%d.%d",
		     &version, &patchlevel, &sublevel);
	if (err != 3) {
		pr_debug("Unable to get kernel version from /proc/version_signature '%s'\n",
			 line);
		goto errout;
	}

	*puint = (version << 16) + (patchlevel << 8) + sublevel;
	err = 0;
errout:
	free(line);
	return err;
}

int
fetch_kernel_version(unsigned int *puint, char *str,
		     size_t str_size)
{
	struct utsname utsname;
	int version, patchlevel, sublevel, err;
	bool int_ver_ready = false;

	if (access("/proc/version_signature", R_OK) == 0)
		if (!fetch_ubuntu_kernel_version(puint))
			int_ver_ready = true;

	if (uname(&utsname))
		return -1;

	if (str && str_size) {
		strncpy(str, utsname.release, str_size);
		str[str_size - 1] = '\0';
	}

	if (!puint || int_ver_ready)
		return 0;

	err = sscanf(utsname.release, "%d.%d.%d",
		     &version, &patchlevel, &sublevel);

	if (err != 3) {
		pr_debug("Unable to get kernel version from uname '%s'\n",
			 utsname.release);
		return -1;
	}

	*puint = (version << 16) + (patchlevel << 8) + sublevel;
	return 0;
}

const char *perf_tip(const char *dirpath)
{
	struct strlist *tips;
	struct str_node *node;
	char *tip = NULL;
	struct strlist_config conf = {
		.dirname = dirpath,
		.file_only = true,
	};

	tips = strlist__new("tips.txt", &conf);
	if (tips == NULL)
		return errno == ENOENT ? NULL :
			"Tip: check path of tips.txt or get more memory! ;-p";

	if (strlist__nr_entries(tips) == 0)
		goto out;

	node = strlist__entry(tips, random() % strlist__nr_entries(tips));
	if (asprintf(&tip, "Tip: %s", node->s) < 0)
		tip = (char *)"Tip: get more memory! ;-)";

out:
	strlist__delete(tips);

	return tip;
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1aed2671	2	#include "../perf.h"
4cf40131	3	#include "util.h"
84f5d36f	4	#include "debug.h"
cd0cfad7	5	#include <api/fs/fs.h>
69e3f52d	6	#include <sys/mman.h>
7a8ef4c4	7	#include <sys/stat.h>
07bc5c69	8	#include <sys/utsname.h>
76b31a29	9	#include <dirent.h>
fd20e811	10	#include <inttypes.h>
9607ad3a	11	#include <signal.h>
dc4552bf ACM	12	#include <stdio.h>
dc4552bf ACM	13	#include <stdlib.h>
cef82c9f JO	14	#include <string.h>
cef82c9f JO	15	#include <errno.h>
1a47245d	16	#include <limits.h>
838d1452	17	#include <linux/kernel.h>
c339b1a9	18	#include <linux/log2.h>
bd48c63e	19	#include <linux/time64.h>
9398c484	20	#include <unistd.h>
14cbfbeb	21	#include "strlist.h"
23aadb1f	22
1aed2671 JR	23	/*
	24	* XXX We need to find a better place for these things...
	25	*/
0c1fe6b2	26	unsigned int page_size;
2b1b7100	27	int cacheline_size;
0c1fe6b2	28
a29d5c9b ACM	29	int sysctl_perf_event_max_stack = PERF_MAX_STACK_DEPTH;
a29d5c9b ACM	30	int sysctl_perf_event_max_contexts_per_stack = PERF_MAX_CONTEXTS_PER_STACK;
4cb93446	31
0c6332e9 ACM	32	bool test_attr__enabled;
0c6332e9 ACM	33
1aed2671	34	bool perf_host = true;
c4a7dca9	35	bool perf_guest = false;
1aed2671 JR	36
	37	void event_attr_init(struct perf_event_attr *attr)
	38	{
	39	if (!perf_host)
	40	attr->exclude_host = 1;
	41	if (!perf_guest)
	42	attr->exclude_guest = 1;
7e1ccd38 SE	43	/* to capture ABI version */
7e1ccd38 SE	44	attr->size = sizeof(*attr);
1aed2671 JR	45	}
1aed2671 JR	46
4cf40131 ACM	47	int mkdir_p(char *path, mode_t mode)
	48	{
	49	struct stat st;
	50	int err;
	51	char *d = path;
	52
	53	if (*d != '/')
	54	return -1;
	55
	56	if (stat(path, &st) == 0)
	57	return 0;
	58
	59	while (*++d == '/');
	60
	61	while ((d = strchr(d, '/'))) {
	62	*d = '\0';
	63	err = stat(path, &st) && mkdir(path, mode);
	64	*d++ = '/';
	65	if (err)
	66	return -1;
	67	while (*d == '/')
	68	++d;
	69	}
	70	return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
	71	}
	72
9a9c733d	73	int rm_rf(const char *path)
0b1de0be NK	74	{
	75	DIR *dir;
	76	int ret = 0;
	77	struct dirent *d;
	78	char namebuf[PATH_MAX];
	79
	80	dir = opendir(path);
	81	if (dir == NULL)
	82	return 0;
	83
	84	while ((d = readdir(dir)) != NULL && !ret) {
	85	struct stat statbuf;
	86
	87	if (!strcmp(d->d_name, ".") \|\| !strcmp(d->d_name, ".."))
	88	continue;
	89
	90	scnprintf(namebuf, sizeof(namebuf), "%s/%s",
	91	path, d->d_name);
	92
2a1ef032 MH	93	/* We have to check symbolic link itself */
2a1ef032 MH	94	ret = lstat(namebuf, &statbuf);
0b1de0be NK	95	if (ret < 0) {
	96	pr_debug("stat failed: %s\n", namebuf);
	97	break;
	98	}
	99
2a1ef032	100	if (S_ISDIR(statbuf.st_mode))
0b1de0be	101	ret = rm_rf(namebuf);
2a1ef032 MH	102	else
2a1ef032 MH	103	ret = unlink(namebuf);
0b1de0be NK	104	}
	105	closedir(dir);
	106
	107	if (ret < 0)
	108	return ret;
	109
	110	return rmdir(path);
	111	}
	112
e1ce726e MH	113	/* A filter which removes dot files */
	114	bool lsdir_no_dot_filter(const char name __maybe_unused, struct dirent d)
	115	{
	116	return d->d_name[0] != '.';
	117	}
	118
	119	/* lsdir reads a directory and store it in strlist */
	120	struct strlist lsdir(const char name,
	121	bool (filter)(const char , struct dirent *))
	122	{
	123	struct strlist *list = NULL;
	124	DIR *dir;
	125	struct dirent *d;
	126
	127	dir = opendir(name);
	128	if (!dir)
	129	return NULL;
	130
	131	list = strlist__new(NULL, NULL);
	132	if (!list) {
357a54f3	133	errno = ENOMEM;
e1ce726e MH	134	goto out;
	135	}
	136
	137	while ((d = readdir(dir)) != NULL) {
	138	if (!filter \|\| filter(name, d))
	139	strlist__add(list, d->d_name);
	140	}
	141
	142	out:
	143	closedir(dir);
	144	return list;
	145	}
	146
f045b8c4	147	static int slow_copyfile(const char from, const char to, struct nsinfo *nsi)
9e201442	148	{
9a17d726	149	int err = -1;
9e201442 ACM	150	char *line = NULL;
9e201442 ACM	151	size_t n;
f045b8c4 KJ	152	FILE from_fp, to_fp;
f045b8c4 KJ	153	struct nscookie nsc;
9e201442	154
f045b8c4 KJ	155	nsinfo__mountns_enter(nsi, &nsc);
	156	from_fp = fopen(from, "r");
	157	nsinfo__mountns_exit(&nsc);
9e201442 ACM	158	if (from_fp == NULL)
	159	goto out;
	160
	161	to_fp = fopen(to, "w");
	162	if (to_fp == NULL)
	163	goto out_fclose_from;
	164
	165	while (getline(&line, &n, from_fp) > 0)
	166	if (fputs(line, to_fp) == EOF)
	167	goto out_fclose_to;
	168	err = 0;
	169	out_fclose_to:
	170	fclose(to_fp);
	171	free(line);
	172	out_fclose_from:
	173	fclose(from_fp);
	174	out:
	175	return err;
	176	}
	177
9c9f5a2f NK	178	int copyfile_offset(int ifd, loff_t off_in, int ofd, loff_t off_out, u64 size)
	179	{
	180	void *ptr;
	181	loff_t pgoff;
	182
	183	pgoff = off_in & ~(page_size - 1);
	184	off_in -= pgoff;
	185
	186	ptr = mmap(NULL, off_in + size, PROT_READ, MAP_PRIVATE, ifd, pgoff);
	187	if (ptr == MAP_FAILED)
	188	return -1;
	189
	190	while (size) {
	191	ssize_t ret = pwrite(ofd, ptr + off_in, size, off_out);
	192	if (ret < 0 && errno == EINTR)
	193	continue;
	194	if (ret <= 0)
	195	break;
	196
	197	size -= ret;
	198	off_in += ret;
	199	off_out -= ret;
	200	}
	201	munmap(ptr, off_in + size);
	202
	203	return size ? -1 : 0;
	204	}
	205
f045b8c4 KJ	206	static int copyfile_mode_ns(const char from, const char to, mode_t mode,
f045b8c4 KJ	207	struct nsinfo *nsi)
4cf40131 ACM	208	{
	209	int fromfd, tofd;
	210	struct stat st;
f045b8c4	211	int err;
d7c72606	212	char tmp = NULL, ptr = NULL;
f045b8c4	213	struct nscookie nsc;
4cf40131	214
f045b8c4 KJ	215	nsinfo__mountns_enter(nsi, &nsc);
	216	err = stat(from, &st);
	217	nsinfo__mountns_exit(&nsc);
	218	if (err)
4cf40131	219	goto out;
f045b8c4	220	err = -1;
4cf40131	221
d7c72606 MV	222	/* extra 'x' at the end is to reserve space for '.' */
	223	if (asprintf(&tmp, "%s.XXXXXXx", to) < 0) {
	224	tmp = NULL;
4cf40131	225	goto out;
d7c72606 MV	226	}
	227	ptr = strrchr(tmp, '/');
	228	if (!ptr)
	229	goto out;
	230	ptr = memmove(ptr + 1, ptr, strlen(ptr) - 1);
	231	*ptr = '.';
4cf40131	232
d7c72606	233	tofd = mkstemp(tmp);
4cf40131	234	if (tofd < 0)
d7c72606 MV	235	goto out;
	236
	237	if (fchmod(tofd, mode))
	238	goto out_close_to;
	239
	240	if (st.st_size == 0) { /* /proc? do it slowly... */
f045b8c4	241	err = slow_copyfile(from, tmp, nsi);
d7c72606 MV	242	goto out_close_to;
	243	}
	244
f045b8c4	245	nsinfo__mountns_enter(nsi, &nsc);
d7c72606	246	fromfd = open(from, O_RDONLY);
f045b8c4	247	nsinfo__mountns_exit(&nsc);
d7c72606 MV	248	if (fromfd < 0)
d7c72606 MV	249	goto out_close_to;
4cf40131	250
9c9f5a2f	251	err = copyfile_offset(fromfd, 0, tofd, 0, st.st_size);
4cf40131	252
4cf40131	253	close(fromfd);
d7c72606 MV	254	out_close_to:
	255	close(tofd);
	256	if (!err)
	257	err = link(tmp, to);
	258	unlink(tmp);
4cf40131	259	out:
d7c72606	260	free(tmp);
4cf40131 ACM	261	return err;
4cf40131 ACM	262	}
c82ee828	263
f045b8c4 KJ	264	int copyfile_ns(const char from, const char to, struct nsinfo *nsi)
	265	{
	266	return copyfile_mode_ns(from, to, 0755, nsi);
	267	}
	268
	269	int copyfile_mode(const char from, const char to, mode_t mode)
	270	{
	271	return copyfile_mode_ns(from, to, mode, NULL);
	272	}
	273
9a17d726 AH	274	int copyfile(const char from, const char to)
	275	{
	276	return copyfile_mode(from, to, 0755);
	277	}
	278
bc3a502b	279	static ssize_t ion(bool is_read, int fd, void *buf, size_t n)
1e7972cc ACM	280	{
1e7972cc ACM	281	void *buf_start = buf;
838d1452	282	size_t left = n;
1e7972cc	283
838d1452	284	while (left) {
7c724405	285	/* buf must be treated as const if !is_read. */
bc3a502b JO	286	ssize_t ret = is_read ? read(fd, buf, left) :
bc3a502b JO	287	write(fd, buf, left);
1e7972cc	288
e148c760 NK	289	if (ret < 0 && errno == EINTR)
e148c760 NK	290	continue;
1e7972cc ACM	291	if (ret <= 0)
	292	return ret;
	293
838d1452 JO	294	left -= ret;
838d1452 JO	295	buf += ret;
1e7972cc ACM	296	}
1e7972cc ACM	297
838d1452 JO	298	BUG_ON((size_t)(buf - buf_start) != n);
838d1452 JO	299	return n;
1e7972cc	300	}
61e04b33	301
bc3a502b JO	302	/*
	303	* Read exactly 'n' bytes or return an error.
	304	*/
	305	ssize_t readn(int fd, void *buf, size_t n)
	306	{
	307	return ion(true, fd, buf, n);
	308	}
	309
	310	/*
	311	* Write exactly 'n' bytes or return an error.
	312	*/
7c724405	313	ssize_t writen(int fd, const void *buf, size_t n)
bc3a502b	314	{
7c724405 DCC	315	/* ion does not modify buf. */
7c724405 DCC	316	return ion(false, fd, (void *)buf, n);
bc3a502b JO	317	}
bc3a502b JO	318
61e04b33 ACM	319	size_t hex_width(u64 v)
	320	{
	321	size_t n = 1;
	322
	323	while ((v >>= 4))
	324	++n;
	325
	326	return n;
	327	}
dc4552bf	328
b2aff5f6 JO	329	static int hex(char ch)
	330	{
	331	if ((ch >= '0') && (ch <= '9'))
	332	return ch - '0';
	333	if ((ch >= 'a') && (ch <= 'f'))
	334	return ch - 'a' + 10;
	335	if ((ch >= 'A') && (ch <= 'F'))
	336	return ch - 'A' + 10;
	337	return -1;
	338	}
	339
	340	/*
	341	* While we find nice hex chars, build a long_val.
	342	* Return number of chars processed.
	343	*/
	344	int hex2u64(const char ptr, u64 long_val)
	345	{
	346	const char *p = ptr;
	347	*long_val = 0;
	348
	349	while (*p) {
	350	const int hex_val = hex(*p);
	351
	352	if (hex_val < 0)
	353	break;
	354
	355	long_val = (long_val << 4) \| hex_val;
	356	p++;
	357	}
	358
	359	return p - ptr;
	360	}
	361
1a47245d AH	362	int perf_event_paranoid(void)
1a47245d AH	363	{
1a47245d AH	364	int value;
1a47245d AH	365
ce27309f	366	if (sysctl__read_int("kernel/perf_event_paranoid", &value))
1a47245d AH	367	return INT_MAX;
	368
	369	return value;
	370	}
d18acd15 WN	371	static int
	372	fetch_ubuntu_kernel_version(unsigned int *puint)
	373	{
	374	ssize_t len;
	375	size_t line_len = 0;
	376	char ptr, line = NULL;
	377	int version, patchlevel, sublevel, err;
44b58e06	378	FILE *vsig;
d18acd15	379
44b58e06 ACM	380	if (!puint)
	381	return 0;
	382
	383	vsig = fopen("/proc/version_signature", "r");
d18acd15 WN	384	if (!vsig) {
	385	pr_debug("Open /proc/version_signature failed: %s\n",
	386	strerror(errno));
	387	return -1;
	388	}
	389
	390	len = getline(&line, &line_len, vsig);
	391	fclose(vsig);
	392	err = -1;
	393	if (len <= 0) {
	394	pr_debug("Reading from /proc/version_signature failed: %s\n",
	395	strerror(errno));
	396	goto errout;
	397	}
	398
	399	ptr = strrchr(line, ' ');
	400	if (!ptr) {
	401	pr_debug("Parsing /proc/version_signature failed: %s\n", line);
	402	goto errout;
	403	}
	404
	405	err = sscanf(ptr + 1, "%d.%d.%d",
	406	&version, &patchlevel, &sublevel);
	407	if (err != 3) {
	408	pr_debug("Unable to get kernel version from /proc/version_signature '%s'\n",
	409	line);
	410	goto errout;
	411	}
	412
44b58e06	413	*puint = (version << 16) + (patchlevel << 8) + sublevel;
d18acd15 WN	414	err = 0;
	415	errout:
	416	free(line);
	417	return err;
	418	}
	419
07bc5c69 WN	420	int
	421	fetch_kernel_version(unsigned int puint, char str,
	422	size_t str_size)
	423	{
	424	struct utsname utsname;
	425	int version, patchlevel, sublevel, err;
d18acd15 WN	426	bool int_ver_ready = false;
	427
	428	if (access("/proc/version_signature", R_OK) == 0)
	429	if (!fetch_ubuntu_kernel_version(puint))
	430	int_ver_ready = true;
07bc5c69 WN	431
	432	if (uname(&utsname))
	433	return -1;
	434
	435	if (str && str_size) {
	436	strncpy(str, utsname.release, str_size);
	437	str[str_size - 1] = '\0';
	438	}
	439
44b58e06 ACM	440	if (!puint \|\| int_ver_ready)
	441	return 0;
	442
07bc5c69 WN	443	err = sscanf(utsname.release, "%d.%d.%d",
	444	&version, &patchlevel, &sublevel);
	445
	446	if (err != 3) {
d18acd15	447	pr_debug("Unable to get kernel version from uname '%s'\n",
07bc5c69 WN	448	utsname.release);
	449	return -1;
	450	}
	451
44b58e06	452	*puint = (version << 16) + (patchlevel << 8) + sublevel;
07bc5c69 WN	453	return 0;
07bc5c69 WN	454	}
14cbfbeb NK	455
	456	const char perf_tip(const char dirpath)
	457	{
	458	struct strlist *tips;
	459	struct str_node *node;
	460	char *tip = NULL;
	461	struct strlist_config conf = {
34b7b0f9 NK	462	.dirname = dirpath,
34b7b0f9 NK	463	.file_only = true,
14cbfbeb NK	464	};
	465
	466	tips = strlist__new("tips.txt", &conf);
34b7b0f9	467	if (tips == NULL)
570eda03 DCC	468	return errno == ENOENT ? NULL :
570eda03 DCC	469	"Tip: check path of tips.txt or get more memory! ;-p";
34b7b0f9 NK	470
34b7b0f9 NK	471	if (strlist__nr_entries(tips) == 0)
14cbfbeb	472	goto out;
14cbfbeb NK	473
	474	node = strlist__entry(tips, random() % strlist__nr_entries(tips));
	475	if (asprintf(&tip, "Tip: %s", node->s) < 0)
	476	tip = (char *)"Tip: get more memory! ;-)";
	477
	478	out:
	479	strlist__delete(tips);
	480
	481	return tip;
	482	}