/* imposter (OO.org Impress viewer) ** Copyright (C) 2003-2005 Gurer Ozen ** This code is free software; you can redistribute it and/or ** modify it under the terms of GNU General Public License. */ #include <config.h> #include "common.h" #include "zip.h" #include <zlib.h> #define _(x) x typedef unsigned long ulong; enum { ZIP_OK = 0, ZIP_NOMEM, ZIP_NOSIG, ZIP_BADZIP, ZIP_NOMULTI, ZIP_EOPEN, ZIP_EREAD, ZIP_NOFILE }; struct zipfile { struct zipfile *next; char *name; ulong crc; ulong zip_size; ulong real_size; ulong pos; }; struct zip_struct { FILE *f; struct zipfile *files; ulong cd_pos; ulong cd_size; ulong cd_offset; ulong head_size; ulong rem_size; ulong nr_files; }; char * zip_error (int err) { char *ret; switch (err) { case ZIP_OK: ret = _("No error"); break; case ZIP_NOMEM: ret = _("Not enough memory"); break; case ZIP_NOSIG: ret = _("Cannot find ZIP signature"); break; case ZIP_BADZIP: ret = _("Invalid ZIP file"); break; case ZIP_NOMULTI: ret = _("Multi file ZIPs are not supported"); break; case ZIP_EOPEN: ret = _("Cannot open the file"); break; case ZIP_EREAD: ret = _("Cannot read data from file"); break; case ZIP_NOFILE: ret = _("Cannot find file in the ZIP archive"); break; default: ret = _("Unknown error"); break; } return ret; } static int find_cd (zip *z) { FILE *f; char *buf; ulong size, pos, i, flag; f = z->f; if (fseek (f, 0, SEEK_END) != 0) return 1; size = ftell (f); if (size < 0xffff) pos = 0; else pos = size - 0xffff; buf = malloc (size - pos + 1); if (!buf) return 1; if (fseek (f, pos, SEEK_SET) != 0) { free (buf); return 1; } if (fread (buf, size - pos, 1, f) != 1) { free (buf); return 1; } flag = 0; for (i = size - pos - 3; i > 0; i--) { if (buf[i] == 0x50 && buf[i+1] == 0x4b && buf[i+2] == 0x05 && buf[i+3] == 0x06) { z->cd_pos = i + pos; flag = 1; break; } } free (buf); if (flag != 1) return 1; return 0; } static unsigned long get_long (unsigned char *buf) { return buf[0] + (buf[1] << 8) + (buf[2] << 16) + (buf[3] << 24); } static unsigned long get_word (unsigned char *buf) { return buf[0] + (buf[1] << 8); } static int list_files (zip *z) { unsigned char buf[46]; struct zipfile *zfile; ulong pat, fn_size; int nr = 0; pat = z->cd_offset; while (nr < z->nr_files) { fseek (z->f, pat + z->head_size, SEEK_SET); if (fread (buf, 46, 1, z->f) != 1) return ZIP_EREAD; if (get_long (buf) != 0x02014b50) return ZIP_BADZIP; zfile = malloc (sizeof (struct zipfile)); if (!zfile) return ZIP_NOMEM; memset (zfile, 0, sizeof (struct zipfile)); zfile->crc = get_long (buf + 16); zfile->zip_size = get_long (buf + 20); zfile->real_size = get_long (buf + 24); fn_size = get_word (buf + 28); zfile->pos = get_long (buf + 42); zfile->name = malloc (fn_size + 1); if (!zfile->name) { free (zfile); return ZIP_NOMEM; } fread (zfile->name, fn_size, 1, z->f); zfile->name[fn_size] = '\0'; zfile->next = z->files; z->files = zfile; pat += 0x2e + fn_size + get_word (buf + 30) + get_word (buf + 32); nr++; } return ZIP_OK; } zip * zip_open (const char *fname, int *err) { unsigned char buf[22]; zip *z; FILE *f; f = fopen (fname, "rb"); if (NULL == f) { *err = ZIP_EOPEN; return NULL; } z = malloc (sizeof (zip)); memset (z, 0, sizeof (zip)); z->f = f; if (find_cd (z)) { zip_close (z); *err = ZIP_NOSIG; return NULL; } fseek (f, z->cd_pos, SEEK_SET); if (fread (buf, 22, 1, f) != 1) { zip_close (z); *err = ZIP_EREAD; return NULL; } z->nr_files = get_word (buf + 10); if (get_word (buf + 8) != z->nr_files) { zip_close (z); *err = ZIP_NOMULTI; return NULL; } z->cd_size = get_long (buf + 12); z->cd_offset = get_long (buf + 16); z->rem_size = get_word (buf + 20); z->head_size = z->cd_pos - (z->cd_offset + z->cd_size); *err = list_files (z); if (*err != ZIP_OK) { zip_close (z); return NULL; } *err = ZIP_OK; return z; } void zip_close (zip *z) { struct zipfile *zfile, *tmp; zfile = z->files; while (zfile) { tmp = zfile->next; if (zfile->name) free (zfile->name); free (zfile); zfile = tmp; } z->files = NULL; if (z->f) fclose (z->f); z->f = NULL; } static struct zipfile * find_file (zip *z, const char *name) { struct zipfile *zfile; zfile = z->files; while (zfile) { if (strcmp (zfile->name, name) == 0) return zfile; zfile = zfile->next; } return NULL; } static int seek_file (zip *z, struct zipfile *zfile) { unsigned char buf[30]; fseek (z->f, zfile->pos + z->head_size, SEEK_SET); if (fread (buf, 30, 1, z->f) != 1) return ZIP_EREAD; if (get_long (buf) != 0x04034b50) return ZIP_BADZIP; fseek (z->f, get_word (buf + 26) + get_word (buf + 28), SEEK_CUR); return ZIP_OK; } iks * zip_load_xml (zip *z, const char *name, int *err) { iksparser *prs; char *real_buf; iks *x; struct zipfile *zfile; *err = ZIP_OK; zfile = find_file (z, name); if (!zfile) { *err = ZIP_NOFILE; return NULL; } seek_file (z, zfile); real_buf = malloc (zfile->real_size + 1); if (zfile->zip_size < zfile->real_size) { char *zip_buf; z_stream zs; zs.zalloc = NULL; zs.zfree = NULL; zs.opaque = NULL; zip_buf = malloc (zfile->zip_size); fread (zip_buf, zfile->zip_size, 1, z->f); zs.next_in = zip_buf; zs.avail_in = zfile->zip_size; zs.next_out = real_buf; zs.avail_out = zfile->real_size; inflateInit2 (&zs, -MAX_WBITS); inflate (&zs, Z_FINISH); inflateEnd (&zs); free (zip_buf); } else { fread (real_buf, zfile->real_size, 1, z->f); } real_buf[zfile->real_size] = '\0'; prs = iks_dom_new (&x); iks_parse (prs, real_buf, zfile->real_size, 1); iks_parser_delete (prs); free (real_buf); return x; } unsigned long zip_get_size (zip *z, const char *name) { struct zipfile *zf; zf = find_file (z, name); if (!zf) return 0; return zf->real_size; } int zip_load (zip *z, const char *name, char *buf) { struct zipfile *zfile; zfile = find_file (z, name); if (!zfile) return ZIP_NOFILE; seek_file (z, zfile); if (zfile->zip_size < zfile->real_size) { char *zip_buf; z_stream zs; zs.zalloc = NULL; zs.zfree = NULL; zs.opaque = NULL; zip_buf = malloc (zfile->zip_size); fread (zip_buf, zfile->zip_size, 1, z->f); zs.next_in = zip_buf; zs.avail_in = zfile->zip_size; zs.next_out = buf; zs.avail_out = zfile->real_size; inflateInit2 (&zs, -MAX_WBITS); inflate (&zs, Z_FINISH); inflateEnd (&zs); free (zip_buf); } else { fread (buf, zfile->real_size, 1, z->f); } return ZIP_OK; }