The assumption is that this area does not change.
*/
-#include <sys/types.h>
+#include "qemu/osdep.h"
#include <sys/param.h>
#include <dirent.h>
-#include <unistd.h>
-#include <stdlib.h>
-#include <string.h>
-#include <errno.h>
-#include <stdio.h>
-#include "qemu-common.h"
+#include "qemu/cutils.h"
+#include "qemu/path.h"
+#include "qemu/thread.h"
-struct pathelem
-{
- /* Name of this, eg. lib */
- char *name;
- /* Full path name, eg. /usr/gnemul/x86-linux/lib. */
- char *pathname;
- struct pathelem *parent;
- /* Children */
- unsigned int num_entries;
- struct pathelem *entries[0];
-};
-
-static struct pathelem *base;
-
-/* First N chars of S1 match S2, and S2 is N chars long. */
-static int strneq(const char *s1, unsigned int n, const char *s2)
-{
- unsigned int i;
-
- for (i = 0; i < n; i++)
- if (s1[i] != s2[i])
- return 0;
- return s2[i] == 0;
-}
-
-static struct pathelem *add_entry(struct pathelem *root, const char *name,
- unsigned type);
+static const char *base;
+static GHashTable *hash;
+static QemuMutex lock;
-static struct pathelem *new_entry(const char *root,
- struct pathelem *parent,
- const char *name)
-{
- struct pathelem *new = g_malloc(sizeof(*new));
- new->name = g_strdup(name);
- new->pathname = g_strdup_printf("%s/%s", root, name);
- new->num_entries = 0;
- return new;
-}
-
-#define streq(a,b) (strcmp((a), (b)) == 0)
-
-/* Not all systems provide this feature */
-#if defined(DT_DIR) && defined(DT_UNKNOWN) && defined(DT_LNK)
-# define dirent_type(dirent) ((dirent)->d_type)
-# define is_dir_maybe(type) \
- ((type) == DT_DIR || (type) == DT_UNKNOWN || (type) == DT_LNK)
-#else
-# define dirent_type(dirent) (1)
-# define is_dir_maybe(type) (type)
-#endif
-
-static struct pathelem *add_dir_maybe(struct pathelem *path)
+void init_paths(const char *prefix)
{
- DIR *dir;
-
- if ((dir = opendir(path->pathname)) != NULL) {
- struct dirent *dirent;
-
- while ((dirent = readdir(dir)) != NULL) {
- if (!streq(dirent->d_name,".") && !streq(dirent->d_name,"..")){
- path = add_entry(path, dirent->d_name, dirent_type(dirent));
- }
- }
- closedir(dir);
+ if (prefix[0] == '\0' || !strcmp(prefix, "/")) {
+ return;
}
- return path;
-}
-
-static struct pathelem *add_entry(struct pathelem *root, const char *name,
- unsigned type)
-{
- struct pathelem **e;
-
- root->num_entries++;
-
- root = g_realloc(root, sizeof(*root)
- + sizeof(root->entries[0])*root->num_entries);
- e = &root->entries[root->num_entries-1];
- *e = new_entry(root->pathname, root, name);
- if (is_dir_maybe(type)) {
- *e = add_dir_maybe(*e);
+ if (prefix[0] == '/') {
+ base = g_strdup(prefix);
+ } else {
+ char *cwd = g_get_current_dir();
+ base = g_build_filename(cwd, prefix, NULL);
+ g_free(cwd);
}
- return root;
-}
-
-/* This needs to be done after tree is stabilized (ie. no more reallocs!). */
-static void set_parents(struct pathelem *child, struct pathelem *parent)
-{
- unsigned int i;
-
- child->parent = parent;
- for (i = 0; i < child->num_entries; i++)
- set_parents(child->entries[i], child);
+ hash = g_hash_table_new(g_str_hash, g_str_equal);
+ qemu_mutex_init(&lock);
}
-/* FIXME: Doesn't handle DIR/.. where DIR is not in emulated dir. */
-static const char *
-follow_path(const struct pathelem *cursor, const char *name)
-{
- unsigned int i, namelen;
-
- name += strspn(name, "/");
- namelen = strcspn(name, "/");
-
- if (namelen == 0)
- return cursor->pathname;
-
- if (strneq(name, namelen, ".."))
- return follow_path(cursor->parent, name + namelen);
-
- if (strneq(name, namelen, "."))
- return follow_path(cursor, name + namelen);
-
- for (i = 0; i < cursor->num_entries; i++)
- if (strneq(name, namelen, cursor->entries[i]->name))
- return follow_path(cursor->entries[i], name + namelen);
-
- /* Not found */
- return NULL;
-}
-
-void init_paths(const char *prefix)
+/* Look for path in emulation dir, otherwise return name. */
+const char *path(const char *name)
{
- char pref_buf[PATH_MAX];
-
- if (prefix[0] == '\0' ||
- !strcmp(prefix, "/"))
- return;
+ gpointer key, value;
+ const char *ret;
- if (prefix[0] != '/') {
- char *cwd = getcwd(NULL, 0);
- size_t pref_buf_len = sizeof(pref_buf);
+ /* Only do absolute paths: quick and dirty, but should mostly be OK. */
+ if (!base || !name || name[0] != '/') {
+ return name;
+ }
- if (!cwd)
- abort();
- pstrcpy(pref_buf, sizeof(pref_buf), cwd);
- pstrcat(pref_buf, pref_buf_len, "/");
- pstrcat(pref_buf, pref_buf_len, prefix);
- free(cwd);
- } else
- pstrcpy(pref_buf, sizeof(pref_buf), prefix + 1);
+ qemu_mutex_lock(&lock);
- base = new_entry("", NULL, pref_buf);
- base = add_dir_maybe(base);
- if (base->num_entries == 0) {
- g_free(base->pathname);
- g_free(base->name);
- g_free(base);
- base = NULL;
+ /* Have we looked up this file before? */
+ if (g_hash_table_lookup_extended(hash, name, &key, &value)) {
+ ret = value ? value : name;
} else {
- set_parents(base, base);
+ char *save = g_strdup(name);
+ char *full = g_build_filename(base, name, NULL);
+
+ /* Look for the path; record the result, pass or fail. */
+ if (access(full, F_OK) == 0) {
+ /* Exists. */
+ g_hash_table_insert(hash, save, full);
+ ret = full;
+ } else {
+ /* Does not exist. */
+ g_free(full);
+ g_hash_table_insert(hash, save, NULL);
+ ret = name;
+ }
}
-}
-
-/* Look for path in emulation dir, otherwise return name. */
-const char *path(const char *name)
-{
- /* Only do absolute paths: quick and dirty, but should mostly be OK.
- Could do relative by tracking cwd. */
- if (!base || !name || name[0] != '/')
- return name;
- return follow_path(base, name) ?: name;
+ qemu_mutex_unlock(&lock);
+ return ret;
}
projects / mirror_qemu.git / blobdiff