Avoid stat call to determine is_directory if possible

On Linux and OS X, we can determine if an entry obtained through a readdir()
call is a directory without also having to stat it. This can save a
significant number of syscalls. The performance increase isn't dramatic, but
it could be on some platforms (e.g. Cygwin) so it shouldn't hurt to use this
unconditionally where supported.

Signed-off-by: Dan McGee <dan@archlinux.org>
This commit is contained in:
Dan McGee 2010-10-05 11:44:32 -05:00
parent bef19a266b
commit dff73a2a69

View file

@ -108,13 +108,28 @@ static int dirlist_from_tar(const char *archive, alpm_list_t **dirlist)
return(0);
}
static int is_dir(const char *path, struct dirent *entry)
{
#ifdef DT_DIR
return(entry->d_type == DT_DIR);
#else
char buffer[PATH_MAX];
snprintf(buffer, PATH_MAX, "%s/%s", path, entry->d_name);
struct stat sbuf;
if (!stat(buffer, &sbuf)) {
return(S_ISDIR(sbuf.st_mode));
}
return(0);
#endif
}
/* create list of directories in db */
static int dirlist_from_fs(const char *syncdbpath, alpm_list_t **dirlist)
{
DIR *dbdir;
struct dirent *ent = NULL;
struct stat sbuf;
char path[PATH_MAX];
dbdir = opendir(syncdbpath);
if (dbdir != NULL) {
@ -127,9 +142,7 @@ static int dirlist_from_fs(const char *syncdbpath, alpm_list_t **dirlist)
continue;
}
/* stat the entry, make sure it's a directory */
snprintf(path, PATH_MAX, "%s%s", syncdbpath, name);
if(stat(path, &sbuf) != 0 || !S_ISDIR(sbuf.st_mode)) {
if(!is_dir(syncdbpath, ent)) {
continue;
}
@ -353,8 +366,6 @@ int _alpm_db_populate(pmdb_t *db)
{
int count = 0;
struct dirent *ent = NULL;
struct stat sbuf;
char path[PATH_MAX];
const char *dbpath;
DIR *dbdir;
@ -374,9 +385,7 @@ int _alpm_db_populate(pmdb_t *db)
if(strcmp(name, ".") == 0 || strcmp(name, "..") == 0) {
continue;
}
/* stat the entry, make sure it's a directory */
snprintf(path, PATH_MAX, "%s%s", dbpath, name);
if(stat(path, &sbuf) != 0 || !S_ISDIR(sbuf.st_mode)) {
if(!is_dir(dbpath, ent)) {
continue;
}