Mercurial > repos > blastem
view zip.c @ 1569:0ec89dadb36d
Add code for loading PNG images. Added 360 controller image. WIP work on gamepad mapping UI
author | Michael Pavone <pavone@retrodev.com> |
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date | Thu, 19 Apr 2018 00:51:10 -0700 |
parents | 092675db4f37 |
children | 7121daaa48c2 |
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#include <stdio.h> #include <stdlib.h> #include <stddef.h> #include <string.h> #include "util.h" #include "zip.h" #ifndef DISABLE_ZLIB #include "zlib/zlib.h" #endif static const char cdfd_magic[4] = {'P', 'K', 1, 2}; static const char eocd_magic[4] = {'P', 'K', 5, 6}; #define MIN_EOCD_SIZE 22 #define MIN_CDFD_SIZE 46 #define ZIP_MAX_EOCD_OFFSET (64*1024+MIN_EOCD_SIZE) enum { ZIP_STORE = 0, ZIP_DEFLATE = 8 }; zip_file *zip_open(char *filename) { FILE *f = fopen(filename, "rb"); if (!f) { return NULL; } long fsize = file_size(f); if (fsize < MIN_EOCD_SIZE) { //too small to be a zip file goto fail; } long max_offset = fsize > ZIP_MAX_EOCD_OFFSET ? ZIP_MAX_EOCD_OFFSET : fsize; fseek(f, -max_offset, SEEK_END); uint8_t *buf = malloc(max_offset); if (max_offset != fread(buf, 1, max_offset, f)) { goto fail; } long current_offset; uint32_t cd_start, cd_size; uint16_t cd_count; for (current_offset = max_offset - MIN_EOCD_SIZE; current_offset >= 0; current_offset--) { if (memcmp(eocd_magic, buf + current_offset, sizeof(eocd_magic))) { continue; } uint16_t comment_size = buf[current_offset + 20] | buf[current_offset + 21] << 8; if (comment_size != (max_offset - current_offset - MIN_EOCD_SIZE)) { continue; } cd_start = buf[current_offset + 16] | buf[current_offset + 17] << 8 | buf[current_offset + 18] << 16 | buf[current_offset + 19] << 24; if (cd_start > (fsize - (max_offset - current_offset))) { continue; } cd_size = buf[current_offset + 12] | buf[current_offset + 13] << 8 | buf[current_offset + 14] << 16 | buf[current_offset + 15] << 24; if ((cd_start + cd_size) > (fsize - (max_offset - current_offset))) { continue; } cd_count = buf[current_offset + 10] | buf[current_offset + 11] << 8; break; } free(buf); if (current_offset < 0) { //failed to find EOCD goto fail; } buf = malloc(cd_size); fseek(f, cd_start, SEEK_SET); if (cd_size != fread(buf, 1, cd_size, f)) { goto fail_free; } zip_entry *entries = calloc(cd_count, sizeof(zip_entry)); uint32_t cd_max_last = cd_size - MIN_CDFD_SIZE; zip_entry *cur_entry = entries; for (uint32_t off = 0; cd_count && off <= cd_max_last; cur_entry++, cd_count--) { if (memcmp(buf + off, cdfd_magic, sizeof(cdfd_magic))) { goto fail_entries; } uint32_t name_length = buf[off + 28] | buf[off + 29] << 8; uint32_t extra_length = buf[off + 30] | buf[off + 31] << 8; //TODO: verify name length doesn't go past end of CD cur_entry->name = malloc(name_length + 1); memcpy(cur_entry->name, buf + off + MIN_CDFD_SIZE, name_length); cur_entry->name[name_length] = 0; cur_entry->compressed_size = buf[off + 20] | buf[off + 21] << 8 | buf[off + 22] << 16 | buf[off + 23] << 24; cur_entry->size = buf[off + 24] | buf[off + 25] << 8 | buf[off + 26] << 16 | buf[off + 27] << 24; cur_entry->local_header_off = buf[off + 42] | buf[off + 43] << 8 | buf[off + 44] << 16 | buf[off + 45] << 24; cur_entry->compression_method = buf[off + 10] | buf[off + 11] << 8; off += name_length + extra_length + MIN_CDFD_SIZE; } zip_file *z = malloc(sizeof(zip_file)); z->entries = entries; z->file = f; z->num_entries = cur_entry - entries; return z; fail_entries: for (cur_entry--; cur_entry >= entries; cur_entry--) { free(cur_entry->name); } free(entries); fail_free: free(buf); fail: fclose(f); return NULL; } uint8_t *zip_read(zip_file *f, uint32_t index, size_t *out_size) { fseek(f->file, f->entries[index].local_header_off + 26, SEEK_SET); uint8_t tmp[4]; if (sizeof(tmp) != fread(tmp, 1, sizeof(tmp), f->file)) { return NULL; } uint32_t local_variable = (tmp[0] | tmp[1] << 8) + (tmp[2] | tmp[3] << 8); fseek(f->file, f->entries[index].local_header_off + local_variable + 30, SEEK_SET); size_t int_size; if (!out_size) { out_size = &int_size; int_size = f->entries[index].size; } uint8_t *buf = malloc(*out_size); if (*out_size > f->entries[index].size) { *out_size = f->entries[index].size; } switch(f->entries[index].compression_method) { case ZIP_STORE: if (*out_size != fread(buf, 1, *out_size, f->file)) { free(buf); return NULL; } break; #ifndef DISABLE_ZLIB case ZIP_DEFLATE: { //note in unzip.c in zlib/contrib suggests a dummy byte is needed, so we allocate an extra byte here uint8_t *src_buf = malloc(f->entries[index].compressed_size + 1); if (f->entries[index].compressed_size != fread(src_buf, 1, f->entries[index].compressed_size, f->file)) { free(src_buf); return NULL; } uLongf destLen = *out_size; z_stream stream; memset(&stream, 0, sizeof(stream)); stream.avail_in = f->entries[index].compressed_size + 1; stream.next_in = src_buf; stream.next_out = buf; stream.avail_out = *out_size; if (Z_OK == inflateInit2(&stream, -15)) { int result = inflate(&stream, Z_FINISH); *out_size = stream.total_out; free(src_buf); inflateEnd(&stream); if (result != Z_OK && result != Z_STREAM_END && result != Z_BUF_ERROR) { free(buf); return NULL; } } break; #endif } default: free(buf); return NULL; } return buf; } void zip_close(zip_file *f) { fclose(f->file); for (uint32_t i = 0; i < f->num_entries; i++) { free(f->entries[i].name); } free(f->entries); free(f); }