circuitpython/lib/memzip/memzip.c

107 lines
3.1 KiB
C

#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include "py/mpconfig.h"
#include "py/misc.h"
#include "memzip.h"
extern uint8_t memzip_data[];
const MEMZIP_FILE_HDR *memzip_find_file_header(const char *filename) {
const MEMZIP_FILE_HDR *file_hdr = (const MEMZIP_FILE_HDR *)memzip_data;
uint8_t *mem_data;
/* Zip file filenames don't have a leading /, so we strip it off */
if (*filename == '/') {
filename++;
}
while (file_hdr->signature == MEMZIP_FILE_HEADER_SIGNATURE) {
const char *file_hdr_filename = (const char *)&file_hdr[1];
mem_data = (uint8_t *)file_hdr_filename;
mem_data += file_hdr->filename_len;
mem_data += file_hdr->extra_len;
if (!strncmp(file_hdr_filename, filename, file_hdr->filename_len)) {
/* We found a match */
return file_hdr;
}
mem_data += file_hdr->uncompressed_size;
file_hdr = (const MEMZIP_FILE_HDR *)mem_data;
}
return NULL;
}
bool memzip_is_dir(const char *filename) {
const MEMZIP_FILE_HDR *file_hdr = (const MEMZIP_FILE_HDR *)memzip_data;
uint8_t *mem_data;
if (strcmp(filename, "/") == 0) {
// The root directory is a directory.
return true;
}
// Zip filenames don't have a leading /, so we strip it off
if (*filename == '/') {
filename++;
}
size_t filename_len = strlen(filename);
while (file_hdr->signature == MEMZIP_FILE_HEADER_SIGNATURE) {
const char *file_hdr_filename = (const char *)&file_hdr[1];
if (filename_len < file_hdr->filename_len &&
strncmp(file_hdr_filename, filename, filename_len) == 0 &&
file_hdr_filename[filename_len] == '/') {
return true;
}
mem_data = (uint8_t *)file_hdr_filename;
mem_data += file_hdr->filename_len;
mem_data += file_hdr->extra_len;
mem_data += file_hdr->uncompressed_size;
file_hdr = (const MEMZIP_FILE_HDR *)mem_data;
}
return NULL;
}
MEMZIP_RESULT memzip_locate(const char *filename, void **data, size_t *len)
{
const MEMZIP_FILE_HDR *file_hdr = memzip_find_file_header(filename);
if (file_hdr == NULL) {
return MZ_NO_FILE;
}
if (file_hdr->compression_method != 0) {
return MZ_FILE_COMPRESSED;
}
uint8_t *mem_data;
mem_data = (uint8_t *)&file_hdr[1];
mem_data += file_hdr->filename_len;
mem_data += file_hdr->extra_len;
*data = mem_data;
*len = file_hdr->uncompressed_size;
return MZ_OK;
}
MEMZIP_RESULT memzip_stat(const char *path, MEMZIP_FILE_INFO *info) {
const MEMZIP_FILE_HDR *file_hdr = memzip_find_file_header(path);
if (file_hdr == NULL) {
if (memzip_is_dir(path)) {
info->file_size = 0;
info->last_mod_date = 0;
info->last_mod_time = 0;
info->is_dir = 1;
return MZ_OK;
}
return MZ_NO_FILE;
}
info->file_size = file_hdr->uncompressed_size;
info->last_mod_date = file_hdr->last_mod_date;
info->last_mod_time = file_hdr->last_mod_time;
info->is_dir = 0;
return MZ_OK;
}