xref: /third_party/zlib/contrib/minizip/mztools.c (revision 275793ea)
1/*
2  Additional tools for Minizip
3  Code: Xavier Roche '2004
4  License: Same as ZLIB (www.gzip.org)
5*/
6
7/* Code */
8#include <stdio.h>
9#include <stdlib.h>
10#include <string.h>
11#include "zlib.h"
12#include "unzip.h"
13
14#define READ_8(adr)  ((unsigned char)*(adr))
15#define READ_16(adr) ( READ_8(adr) | (READ_8(adr+1) << 8) )
16#define READ_32(adr) ( READ_16(adr) | (READ_16((adr)+2) << 16) )
17
18#define WRITE_8(buff, n) do { \
19  *((unsigned char*)(buff)) = (unsigned char) ((n) & 0xff); \
20} while(0)
21#define WRITE_16(buff, n) do { \
22  WRITE_8((unsigned char*)(buff), n); \
23  WRITE_8(((unsigned char*)(buff)) + 1, (n) >> 8); \
24} while(0)
25#define WRITE_32(buff, n) do { \
26  WRITE_16((unsigned char*)(buff), (n) & 0xffff); \
27  WRITE_16((unsigned char*)(buff) + 2, (n) >> 16); \
28} while(0)
29
30extern int ZEXPORT unzRepair(const char* file,
31                             const char* fileOut,
32                             const char* fileOutTmp,
33                             uLong* nRecovered,
34                             uLong* bytesRecovered)
35{
36  int err = Z_OK;
37  FILE* fpZip = fopen(file, "rb");
38  FILE* fpOut = fopen(fileOut, "wb");
39  FILE* fpOutCD = fopen(fileOutTmp, "wb");
40  if (fpZip != NULL &&  fpOut != NULL) {
41    int entries = 0;
42    uLong totalBytes = 0;
43    char header[30];
44    char filename[1024];
45    char extra[1024];
46    int offset = 0;
47    int offsetCD = 0;
48    while ( fread(header, 1, 30, fpZip) == 30 ) {
49      int currentOffset = offset;
50
51      /* File entry */
52      if (READ_32(header) == 0x04034b50) {
53        unsigned int version = READ_16(header + 4);
54        unsigned int gpflag = READ_16(header + 6);
55        unsigned int method = READ_16(header + 8);
56        unsigned int filetime = READ_16(header + 10);
57        unsigned int filedate = READ_16(header + 12);
58        unsigned int crc = READ_32(header + 14); /* crc */
59        unsigned int cpsize = READ_32(header + 18); /* compressed size */
60        unsigned int uncpsize = READ_32(header + 22); /* uncompressed sz */
61        unsigned int fnsize = READ_16(header + 26); /* file name length */
62        unsigned int extsize = READ_16(header + 28); /* extra field length */
63        filename[0] = extra[0] = '\0';
64
65        /* Header */
66        if (fwrite(header, 1, 30, fpOut) == 30) {
67          offset += 30;
68        } else {
69          err = Z_ERRNO;
70          break;
71        }
72
73        /* Filename */
74        if (fnsize > 0) {
75          if (fnsize < sizeof(filename)) {
76            if (fread(filename, 1, fnsize, fpZip) == fnsize) {
77                if (fwrite(filename, 1, fnsize, fpOut) == fnsize) {
78                offset += fnsize;
79              } else {
80                err = Z_ERRNO;
81                break;
82              }
83            } else {
84              err = Z_ERRNO;
85              break;
86            }
87          } else {
88            err = Z_ERRNO;
89            break;
90          }
91        } else {
92          err = Z_STREAM_ERROR;
93          break;
94        }
95
96        /* Extra field */
97        if (extsize > 0) {
98          if (extsize < sizeof(extra)) {
99            if (fread(extra, 1, extsize, fpZip) == extsize) {
100              if (fwrite(extra, 1, extsize, fpOut) == extsize) {
101                offset += extsize;
102                } else {
103                err = Z_ERRNO;
104                break;
105              }
106            } else {
107              err = Z_ERRNO;
108              break;
109            }
110          } else {
111            err = Z_ERRNO;
112            break;
113          }
114        }
115
116        /* Data */
117        {
118          int dataSize = cpsize;
119          if (dataSize == 0) {
120            dataSize = uncpsize;
121          }
122          if (dataSize > 0) {
123            char* data = malloc(dataSize);
124            if (data != NULL) {
125              if ((int)fread(data, 1, dataSize, fpZip) == dataSize) {
126                if ((int)fwrite(data, 1, dataSize, fpOut) == dataSize) {
127                  offset += dataSize;
128                  totalBytes += dataSize;
129                } else {
130                  err = Z_ERRNO;
131                }
132              } else {
133                err = Z_ERRNO;
134              }
135              free(data);
136              if (err != Z_OK) {
137                break;
138              }
139            } else {
140              err = Z_MEM_ERROR;
141              break;
142            }
143          }
144        }
145
146        /* Central directory entry */
147        {
148          char header[46];
149          char* comment = "";
150          int comsize = (int) strlen(comment);
151          WRITE_32(header, 0x02014b50);
152          WRITE_16(header + 4, version);
153          WRITE_16(header + 6, version);
154          WRITE_16(header + 8, gpflag);
155          WRITE_16(header + 10, method);
156          WRITE_16(header + 12, filetime);
157          WRITE_16(header + 14, filedate);
158          WRITE_32(header + 16, crc);
159          WRITE_32(header + 20, cpsize);
160          WRITE_32(header + 24, uncpsize);
161          WRITE_16(header + 28, fnsize);
162          WRITE_16(header + 30, extsize);
163          WRITE_16(header + 32, comsize);
164          WRITE_16(header + 34, 0);     /* disk # */
165          WRITE_16(header + 36, 0);     /* int attrb */
166          WRITE_32(header + 38, 0);     /* ext attrb */
167          WRITE_32(header + 42, currentOffset);
168          /* Header */
169          if (fwrite(header, 1, 46, fpOutCD) == 46) {
170            offsetCD += 46;
171
172            /* Filename */
173            if (fnsize > 0) {
174              if (fwrite(filename, 1, fnsize, fpOutCD) == fnsize) {
175                offsetCD += fnsize;
176              } else {
177                err = Z_ERRNO;
178                break;
179              }
180            } else {
181              err = Z_STREAM_ERROR;
182              break;
183            }
184
185            /* Extra field */
186            if (extsize > 0) {
187              if (fwrite(extra, 1, extsize, fpOutCD) == extsize) {
188                offsetCD += extsize;
189              } else {
190                err = Z_ERRNO;
191                break;
192              }
193            }
194
195            /* Comment field */
196            if (comsize > 0) {
197              if ((int)fwrite(comment, 1, comsize, fpOutCD) == comsize) {
198                offsetCD += comsize;
199              } else {
200                err = Z_ERRNO;
201                break;
202              }
203            }
204
205
206          } else {
207            err = Z_ERRNO;
208            break;
209          }
210        }
211
212        /* Success */
213        entries++;
214
215      } else {
216        break;
217      }
218    }
219
220    /* Final central directory  */
221    {
222      int entriesZip = entries;
223      char header[22];
224      char* comment = ""; // "ZIP File recovered by zlib/minizip/mztools";
225      int comsize = (int) strlen(comment);
226      if (entriesZip > 0xffff) {
227        entriesZip = 0xffff;
228      }
229      WRITE_32(header, 0x06054b50);
230      WRITE_16(header + 4, 0);    /* disk # */
231      WRITE_16(header + 6, 0);    /* disk # */
232      WRITE_16(header + 8, entriesZip);   /* hack */
233      WRITE_16(header + 10, entriesZip);  /* hack */
234      WRITE_32(header + 12, offsetCD);    /* size of CD */
235      WRITE_32(header + 16, offset);      /* offset to CD */
236      WRITE_16(header + 20, comsize);     /* comment */
237
238      /* Header */
239      if (fwrite(header, 1, 22, fpOutCD) == 22) {
240
241        /* Comment field */
242        if (comsize > 0) {
243          if ((int)fwrite(comment, 1, comsize, fpOutCD) != comsize) {
244            err = Z_ERRNO;
245          }
246        }
247
248      } else {
249        err = Z_ERRNO;
250      }
251    }
252
253    /* Final merge (file + central directory) */
254    fclose(fpOutCD);
255    if (err == Z_OK) {
256      fpOutCD = fopen(fileOutTmp, "rb");
257      if (fpOutCD != NULL) {
258        int nRead;
259        char buffer[8192];
260        while ( (nRead = (int)fread(buffer, 1, sizeof(buffer), fpOutCD)) > 0) {
261          if ((int)fwrite(buffer, 1, nRead, fpOut) != nRead) {
262            err = Z_ERRNO;
263            break;
264          }
265        }
266        fclose(fpOutCD);
267      }
268    }
269
270    /* Close */
271    fclose(fpZip);
272    fclose(fpOut);
273
274    /* Wipe temporary file */
275    (void)remove(fileOutTmp);
276
277    /* Number of recovered entries */
278    if (err == Z_OK) {
279      if (nRecovered != NULL) {
280        *nRecovered = entries;
281      }
282      if (bytesRecovered != NULL) {
283        *bytesRecovered = totalBytes;
284      }
285    }
286  } else {
287    err = Z_STREAM_ERROR;
288  }
289  return err;
290}
291