Libav
cws2fws.c
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1 /*
2  * cws2fws by Alex Beregszaszi
3  * This file is placed in the public domain.
4  * Use the program however you see fit.
5  *
6  * This utility converts compressed Macromedia Flash files to uncompressed ones.
7  */
8 
9 #include "config.h"
10 #include <sys/stat.h>
11 #include <fcntl.h>
12 #include <stdio.h>
13 #include <stdlib.h>
14 #if HAVE_UNISTD_H
15 #include <unistd.h>
16 #endif
17 #if HAVE_IO_H
18 #include <io.h>
19 #endif
20 #include <zlib.h>
21 
22 #ifdef DEBUG
23 #define dbgprintf printf
24 #else
25 #define dbgprintf(...)
26 #endif
27 
28 int main(int argc, char *argv[])
29 {
30  int fd_in, fd_out, comp_len, uncomp_len, i, last_out;
31  char buf_in[1024], buf_out[65536];
32  z_stream zstream;
33  struct stat statbuf;
34  int ret = 1;
35 
36  if (argc < 3) {
37  printf("Usage: %s <infile.swf> <outfile.swf>\n", argv[0]);
38  return 1;
39  }
40 
41  fd_in = open(argv[1], O_RDONLY);
42  if (fd_in < 0) {
43  perror("Error opening input file");
44  return 1;
45  }
46 
47  fd_out = open(argv[2], O_WRONLY | O_CREAT, 00644);
48  if (fd_out < 0) {
49  perror("Error opening output file");
50  close(fd_in);
51  return 1;
52  }
53 
54  if (read(fd_in, &buf_in, 8) != 8) {
55  printf("Header error\n");
56  goto out;
57  }
58 
59  if (buf_in[0] != 'C' || buf_in[1] != 'W' || buf_in[2] != 'S') {
60  printf("Not a compressed flash file\n");
61  goto out;
62  }
63 
64  fstat(fd_in, &statbuf);
65  comp_len = statbuf.st_size;
66  uncomp_len = buf_in[4] | (buf_in[5] << 8) | (buf_in[6] << 16) | (buf_in[7] << 24);
67 
68  printf("Compressed size: %d Uncompressed size: %d\n",
69  comp_len - 4, uncomp_len - 4);
70 
71  // write out modified header
72  buf_in[0] = 'F';
73  if (write(fd_out, &buf_in, 8) < 8) {
74  perror("Error writing output file");
75  goto out;
76  }
77 
78  zstream.zalloc = NULL;
79  zstream.zfree = NULL;
80  zstream.opaque = NULL;
81  inflateInit(&zstream);
82 
83  for (i = 0; i < comp_len - 8;) {
84  int ret, len = read(fd_in, &buf_in, 1024);
85 
86  dbgprintf("read %d bytes\n", len);
87 
88  last_out = zstream.total_out;
89 
90  zstream.next_in = &buf_in[0];
91  zstream.avail_in = len;
92  zstream.next_out = &buf_out[0];
93  zstream.avail_out = 65536;
94 
95  ret = inflate(&zstream, Z_SYNC_FLUSH);
96  if (ret != Z_STREAM_END && ret != Z_OK) {
97  printf("Error while decompressing: %d\n", ret);
98  inflateEnd(&zstream);
99  goto out;
100  }
101 
102  dbgprintf("a_in: %d t_in: %lu a_out: %d t_out: %lu -- %lu out\n",
103  zstream.avail_in, zstream.total_in, zstream.avail_out,
104  zstream.total_out, zstream.total_out - last_out);
105 
106  if (write(fd_out, &buf_out, zstream.total_out - last_out) <
107  zstream.total_out - last_out) {
108  perror("Error writing output file");
109  inflateEnd(&zstream);
110  goto out;
111  }
112 
113  i += len;
114 
115  if (ret == Z_STREAM_END || ret == Z_BUF_ERROR)
116  break;
117  }
118 
119  if (zstream.total_out != uncomp_len - 8) {
120  printf("Size mismatch (%lu != %d), updating header...\n",
121  zstream.total_out, uncomp_len - 8);
122 
123  buf_in[0] = (zstream.total_out + 8) & 0xff;
124  buf_in[1] = ((zstream.total_out + 8) >> 8) & 0xff;
125  buf_in[2] = ((zstream.total_out + 8) >> 16) & 0xff;
126  buf_in[3] = ((zstream.total_out + 8) >> 24) & 0xff;
127 
128  lseek(fd_out, 4, SEEK_SET);
129  if (write(fd_out, &buf_in, 4) < 4) {
130  perror("Error writing output file");
131  inflateEnd(&zstream);
132  goto out;
133  }
134  }
135 
136  ret = 0;
137  inflateEnd(&zstream);
138 out:
139  close(fd_in);
140  close(fd_out);
141  return ret;
142 }
#define dbgprintf(...)
Definition: cws2fws.c:25
NULL
Definition: eval.c:55
int main(int argc, char *argv[])
Definition: cws2fws.c:28
int len
FILE * out
Definition: movenc.c:54