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#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif
#include <dirent.h>
#include <dlfcn.h>
#include <pthread.h>
#include <string.h>
#include <sys/types.h>
#include <unistd.h>
typedef DIR *(*opendir_t)(const char *name);
typedef int (*readdir_r_t)(DIR *dirp, struct dirent *entry, struct dirent **result);
typedef int (*closedir_t)(DIR *dirp);
#define MAX_DIR_SCAN 5000
static pthread_mutex_t data_lock = PTHREAD_MUTEX_INITIALIZER;
static DIR *fast_dir[MAX_DIR_SCAN];
static const char *fast_path_contains[] = {"hdd_0_0", "hdd_1_0", "hdd_2_0", "hdd_3_0", 0};
DIR *opendir(const char *name) {
static opendir_t _opendir = NULL;
DIR *result;
int contains_path, i;
if (!_opendir) {
_opendir = (opendir_t)dlsym(RTLD_NEXT, "opendir");
}
result = _opendir(name);
contains_path = 0;
for (i = 0; fast_path_contains[i]; ++i) {
if (strstr(name, fast_path_contains[i])) {
contains_path = 1;
break;
}
}
if (contains_path) {
pthread_mutex_lock(&data_lock);
for (i = 0; i < MAX_DIR_SCAN; ++i) {
if (fast_dir[i] == NULL) {
fast_dir[i] = result;
break;
}
}
pthread_mutex_unlock(&data_lock);
}
return result;
}
int readdir_r(DIR *dirp, struct dirent *entry, struct dirent **result) {
static readdir_r_t _readdir_r = NULL;
int i, slow;
slow = 1;
pthread_mutex_lock(&data_lock);
for (i = 0; i < MAX_DIR_SCAN; ++i) {
if (fast_dir[i] == dirp) {
slow = 0;
}
}
pthread_mutex_unlock(&data_lock);
if (slow) {
sleep(1);
}
if (!_readdir_r) {
_readdir_r = (readdir_r_t)dlsym(RTLD_NEXT, "readdir_r");
}
return _readdir_r(dirp, entry, result);
}
int closedir(DIR *dirp) {
static closedir_t _closedir = NULL;
int i;
if (!_closedir) {
_closedir = (closedir_t)dlsym(RTLD_NEXT, "closedir");
}
pthread_mutex_lock(&data_lock);
for (i = 0; i < MAX_DIR_SCAN; ++i) {
if (fast_dir[i] == dirp) {
fast_dir[i] = NULL;
break;
}
}
pthread_mutex_unlock(&data_lock);
return _closedir(dirp);
}
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