mongoose/src/fs_packed.c

118 lines
3.3 KiB
C

#include "fmt.h"
#include "fs.h"
#include "str.h"
struct packed_file {
const char *data;
size_t size;
size_t pos;
};
const char *mg_unpack(const char *path, size_t *size, time_t *mtime);
const char *mg_unlist(size_t no);
#if MG_ENABLE_PACKED_FS
#else
const char *mg_unpack(const char *path, size_t *size, time_t *mtime) {
(void) path, (void) size, (void) mtime;
return NULL;
}
const char *mg_unlist(size_t no) {
(void) no;
return NULL;
}
#endif
static int is_dir_prefix(const char *prefix, size_t n, const char *path) {
// MG_INFO(("[%.*s] [%s] %c", (int) n, prefix, path, path[n]));
return n < strlen(path) && strncmp(prefix, path, n) == 0 &&
(n == 0 || path[n] == '/' || path[n - 1] == '/');
}
static int packed_stat(const char *path, size_t *size, time_t *mtime) {
const char *p;
size_t i, n = strlen(path);
if (mg_unpack(path, size, mtime)) return MG_FS_READ; // Regular file
// Scan all files. If `path` is a dir prefix for any of them, it's a dir
for (i = 0; (p = mg_unlist(i)) != NULL; i++) {
if (is_dir_prefix(path, n, p)) return MG_FS_DIR;
}
return 0;
}
static void packed_list(const char *dir, void (*fn)(const char *, void *),
void *userdata) {
char buf[MG_PATH_MAX], tmp[sizeof(buf)];
const char *path, *begin, *end;
size_t i, n = strlen(dir);
tmp[0] = '\0'; // Previously listed entry
for (i = 0; (path = mg_unlist(i)) != NULL; i++) {
if (!is_dir_prefix(dir, n, path)) continue;
begin = &path[n + 1];
end = strchr(begin, '/');
if (end == NULL) end = begin + strlen(begin);
mg_snprintf(buf, sizeof(buf), "%.*s", (int) (end - begin), begin);
buf[sizeof(buf) - 1] = '\0';
// If this entry has been already listed, skip
// NOTE: we're assuming that file list is sorted alphabetically
if (strcmp(buf, tmp) == 0) continue;
fn(buf, userdata); // Not yet listed, call user function
strcpy(tmp, buf); // And save this entry as listed
}
}
static void *packed_open(const char *path, int flags) {
size_t size = 0;
const char *data = mg_unpack(path, &size, NULL);
struct packed_file *fp = NULL;
if (data == NULL) return NULL;
if (flags & MG_FS_WRITE) return NULL;
fp = (struct packed_file *) calloc(1, sizeof(*fp));
fp->size = size;
fp->data = data;
return (void *) fp;
}
static void packed_close(void *fp) {
if (fp != NULL) free(fp);
}
static size_t packed_read(void *fd, void *buf, size_t len) {
struct packed_file *fp = (struct packed_file *) fd;
if (fp->pos + len > fp->size) len = fp->size - fp->pos;
memcpy(buf, &fp->data[fp->pos], len);
fp->pos += len;
return len;
}
static size_t packed_write(void *fd, const void *buf, size_t len) {
(void) fd, (void) buf, (void) len;
return 0;
}
static size_t packed_seek(void *fd, size_t offset) {
struct packed_file *fp = (struct packed_file *) fd;
fp->pos = offset;
if (fp->pos > fp->size) fp->pos = fp->size;
return fp->pos;
}
static bool packed_rename(const char *from, const char *to) {
(void) from, (void) to;
return false;
}
static bool packed_remove(const char *path) {
(void) path;
return false;
}
static bool packed_mkdir(const char *path) {
(void) path;
return false;
}
struct mg_fs mg_fs_packed = {
packed_stat, packed_list, packed_open, packed_close, packed_read,
packed_write, packed_seek, packed_rename, packed_remove, packed_mkdir};