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user: speed up init_paths a bit

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The current init_paths code will attempt to opendir() every single file it
finds.  This can obviously generated a huge number of syscalls with even a
moderately small sysroot that will fail.  Since the readdir() call provides
the file type in the struct itself, use it.  On my system, this prevents
over 1000 syscalls from being made at every invocation of a target binary,
and I only have a C library installed.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Riku Voipio <riku.voipio@nokia.com>
This commit is contained in:
Mike Frysinger 2011-02-07 01:05:56 -05:00 committed by Riku Voipio
parent 737de1d135
commit 2296f194df
1 changed files with 22 additions and 6 deletions
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28
path.c
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@ -38,7 +38,8 @@ static int strneq(const char *s1, unsigned int n, const char *s2)
return s2[i] == 0; return s2[i] == 0;
} }
static struct pathelem *add_entry(struct pathelem *root, const char *name); static struct pathelem *add_entry(struct pathelem *root, const char *name,
unsigned char type);
static struct pathelem *new_entry(const char *root, static struct pathelem *new_entry(const char *root,
struct pathelem *parent, struct pathelem *parent,
@ -56,6 +57,15 @@ static struct pathelem *new_entry(const char *root,
#define streq(a,b) (strcmp((a), (b)) == 0) #define streq(a,b) (strcmp((a), (b)) == 0)
/* Not all systems provide this feature */
#if defined(DT_DIR) && defined(DT_UNKNOWN)
# define dirent_type(dirent) ((dirent)->d_type)
# define is_dir_maybe(type) ((type) == DT_DIR || (type) == DT_UNKNOWN)
#else
# define dirent_type(dirent) (1)
# define is_dir_maybe(type) (type)
#endif
static struct pathelem *add_dir_maybe(struct pathelem *path) static struct pathelem *add_dir_maybe(struct pathelem *path)
{ {
DIR *dir; DIR *dir;
@ -65,7 +75,7 @@ static struct pathelem *add_dir_maybe(struct pathelem *path)
while ((dirent = readdir(dir)) != NULL) { while ((dirent = readdir(dir)) != NULL) {
if (!streq(dirent->d_name,".") && !streq(dirent->d_name,"..")){ if (!streq(dirent->d_name,".") && !streq(dirent->d_name,"..")){
path = add_entry(path, dirent->d_name); path = add_entry(path, dirent->d_name, dirent_type(dirent));
} }
} }
closedir(dir); closedir(dir);
@ -73,16 +83,22 @@ static struct pathelem *add_dir_maybe(struct pathelem *path)
return path; return path;
} }
static struct pathelem *add_entry(struct pathelem *root, const char *name) static struct pathelem *add_entry(struct pathelem *root, const char *name,
unsigned char type)
{ {
struct pathelem **e;
root->num_entries++; root->num_entries++;
root = realloc(root, sizeof(*root) root = realloc(root, sizeof(*root)
+ sizeof(root->entries[0])*root->num_entries); + 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);
}
root->entries[root->num_entries-1] = new_entry(root->pathname, root, name);
root->entries[root->num_entries-1]
= add_dir_maybe(root->entries[root->num_entries-1]);
return root; return root;
} }