1 /*	$NetBSD: mztools.c,v 1.1.1.1 2006/01/14 20:10:58 christos Exp $	*/
2 
3 /*
4   Additional tools for Minizip
5   Code: Xavier Roche '2004
6   License: Same as ZLIB (www.gzip.org)
7 */
8 
9 /* Code */
10 #include <stdio.h>
11 #include <stdlib.h>
12 #include <string.h>
13 #include "zlib.h"
14 #include "unzip.h"
15 
16 #define READ_8(adr)  ((unsigned char)*(adr))
17 #define READ_16(adr) ( READ_8(adr) | (READ_8(adr+1) << 8) )
18 #define READ_32(adr) ( READ_16(adr) | (READ_16((adr)+2) << 16) )
19 
20 #define WRITE_8(buff, n) do { \
21   *((unsigned char*)(buff)) = (unsigned char) ((n) & 0xff); \
22 } while(0)
23 #define WRITE_16(buff, n) do { \
24   WRITE_8((unsigned char*)(buff), n); \
25   WRITE_8(((unsigned char*)(buff)) + 1, (n) >> 8); \
26 } while(0)
27 #define WRITE_32(buff, n) do { \
28   WRITE_16((unsigned char*)(buff), (n) & 0xffff); \
29   WRITE_16((unsigned char*)(buff) + 2, (n) >> 16); \
30 } while(0)
31 
32 extern int ZEXPORT unzRepair(file, fileOut, fileOutTmp, nRecovered, bytesRecovered)
33 const char* file;
34 const char* fileOut;
35 const char* fileOutTmp;
36 uLong* nRecovered;
37 uLong* bytesRecovered;
38 {
39   int err = Z_OK;
40   FILE* fpZip = fopen(file, "rb");
41   FILE* fpOut = fopen(fileOut, "wb");
42   FILE* fpOutCD = fopen(fileOutTmp, "wb");
43   if (fpZip != NULL &&  fpOut != NULL) {
44     int entries = 0;
45     uLong totalBytes = 0;
46     char header[30];
47     char filename[256];
48     char extra[1024];
49     int offset = 0;
50     int offsetCD = 0;
51     while ( fread(header, 1, 30, fpZip) == 30 ) {
52       int currentOffset = offset;
53 
54       /* File entry */
55       if (READ_32(header) == 0x04034b50) {
56         unsigned int version = READ_16(header + 4);
57         unsigned int gpflag = READ_16(header + 6);
58         unsigned int method = READ_16(header + 8);
59         unsigned int filetime = READ_16(header + 10);
60         unsigned int filedate = READ_16(header + 12);
61         unsigned int crc = READ_32(header + 14); /* crc */
62         unsigned int cpsize = READ_32(header + 18); /* compressed size */
63         unsigned int uncpsize = READ_32(header + 22); /* uncompressed sz */
64         unsigned int fnsize = READ_16(header + 26); /* file name length */
65         unsigned int extsize = READ_16(header + 28); /* extra field length */
66         filename[0] = extra[0] = '\0';
67 
68         /* Header */
69         if (fwrite(header, 1, 30, fpOut) == 30) {
70           offset += 30;
71         } else {
72           err = Z_ERRNO;
73           break;
74         }
75 
76         /* Filename */
77         if (fnsize > 0) {
78           if (fread(filename, 1, fnsize, fpZip) == fnsize) {
79             if (fwrite(filename, 1, fnsize, fpOut) == fnsize) {
80               offset += fnsize;
81             } else {
82               err = Z_ERRNO;
83               break;
84             }
85           } else {
86             err = Z_ERRNO;
87             break;
88           }
89         } else {
90           err = Z_STREAM_ERROR;
91           break;
92         }
93 
94         /* Extra field */
95         if (extsize > 0) {
96           if (fread(extra, 1, extsize, fpZip) == extsize) {
97             if (fwrite(extra, 1, extsize, fpOut) == extsize) {
98               offset += extsize;
99             } else {
100               err = Z_ERRNO;
101               break;
102             }
103           } else {
104             err = Z_ERRNO;
105             break;
106           }
107         }
108 
109         /* Data */
110         {
111           int dataSize = cpsize;
112           if (dataSize == 0) {
113             dataSize = uncpsize;
114           }
115           if (dataSize > 0) {
116             char* data = malloc(dataSize);
117             if (data != NULL) {
118               if ((int)fread(data, 1, dataSize, fpZip) == dataSize) {
119                 if ((int)fwrite(data, 1, dataSize, fpOut) == dataSize) {
120                   offset += dataSize;
121                   totalBytes += dataSize;
122                 } else {
123                   err = Z_ERRNO;
124                 }
125               } else {
126                 err = Z_ERRNO;
127               }
128               free(data);
129               if (err != Z_OK) {
130                 break;
131               }
132             } else {
133               err = Z_MEM_ERROR;
134               break;
135             }
136           }
137         }
138 
139         /* Central directory entry */
140         {
141           char header[46];
142           char* comment = "";
143           int comsize = (int) strlen(comment);
144           WRITE_32(header, 0x02014b50);
145           WRITE_16(header + 4, version);
146           WRITE_16(header + 6, version);
147           WRITE_16(header + 8, gpflag);
148           WRITE_16(header + 10, method);
149           WRITE_16(header + 12, filetime);
150           WRITE_16(header + 14, filedate);
151           WRITE_32(header + 16, crc);
152           WRITE_32(header + 20, cpsize);
153           WRITE_32(header + 24, uncpsize);
154           WRITE_16(header + 28, fnsize);
155           WRITE_16(header + 30, extsize);
156           WRITE_16(header + 32, comsize);
157           WRITE_16(header + 34, 0);     /* disk # */
158           WRITE_16(header + 36, 0);     /* int attrb */
159           WRITE_32(header + 38, 0);     /* ext attrb */
160           WRITE_32(header + 42, currentOffset);
161           /* Header */
162           if (fwrite(header, 1, 46, fpOutCD) == 46) {
163             offsetCD += 46;
164 
165             /* Filename */
166             if (fnsize > 0) {
167               if (fwrite(filename, 1, fnsize, fpOutCD) == fnsize) {
168                 offsetCD += fnsize;
169               } else {
170                 err = Z_ERRNO;
171                 break;
172               }
173             } else {
174               err = Z_STREAM_ERROR;
175               break;
176             }
177 
178             /* Extra field */
179             if (extsize > 0) {
180               if (fwrite(extra, 1, extsize, fpOutCD) == extsize) {
181                 offsetCD += extsize;
182               } else {
183                 err = Z_ERRNO;
184                 break;
185               }
186             }
187 
188             /* Comment field */
189             if (comsize > 0) {
190               if ((int)fwrite(comment, 1, comsize, fpOutCD) == comsize) {
191                 offsetCD += comsize;
192               } else {
193                 err = Z_ERRNO;
194                 break;
195               }
196             }
197 
198 
199           } else {
200             err = Z_ERRNO;
201             break;
202           }
203         }
204 
205         /* Success */
206         entries++;
207 
208       } else {
209         break;
210       }
211     }
212 
213     /* Final central directory  */
214     {
215       int entriesZip = entries;
216       char header[22];
217       char* comment = ""; // "ZIP File recovered by zlib/minizip/mztools";
218       int comsize = (int) strlen(comment);
219       if (entriesZip > 0xffff) {
220         entriesZip = 0xffff;
221       }
222       WRITE_32(header, 0x06054b50);
223       WRITE_16(header + 4, 0);    /* disk # */
224       WRITE_16(header + 6, 0);    /* disk # */
225       WRITE_16(header + 8, entriesZip);   /* hack */
226       WRITE_16(header + 10, entriesZip);  /* hack */
227       WRITE_32(header + 12, offsetCD);    /* size of CD */
228       WRITE_32(header + 16, offset);      /* offset to CD */
229       WRITE_16(header + 20, comsize);     /* comment */
230 
231       /* Header */
232       if (fwrite(header, 1, 22, fpOutCD) == 22) {
233 
234         /* Comment field */
235         if (comsize > 0) {
236           if ((int)fwrite(comment, 1, comsize, fpOutCD) != comsize) {
237             err = Z_ERRNO;
238           }
239         }
240 
241       } else {
242         err = Z_ERRNO;
243       }
244     }
245 
246     /* Final merge (file + central directory) */
247     fclose(fpOutCD);
248     if (err == Z_OK) {
249       fpOutCD = fopen(fileOutTmp, "rb");
250       if (fpOutCD != NULL) {
251         int nRead;
252         char buffer[8192];
253         while ( (nRead = (int)fread(buffer, 1, sizeof(buffer), fpOutCD)) > 0) {
254           if ((int)fwrite(buffer, 1, nRead, fpOut) != nRead) {
255             err = Z_ERRNO;
256             break;
257           }
258         }
259         fclose(fpOutCD);
260       }
261     }
262 
263     /* Close */
264     fclose(fpZip);
265     fclose(fpOut);
266 
267     /* Wipe temporary file */
268     (void)remove(fileOutTmp);
269 
270     /* Number of recovered entries */
271     if (err == Z_OK) {
272       if (nRecovered != NULL) {
273         *nRecovered = entries;
274       }
275       if (bytesRecovered != NULL) {
276         *bytesRecovered = totalBytes;
277       }
278     }
279   } else {
280     err = Z_STREAM_ERROR;
281   }
282   return err;
283 }
284