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 
35  if (argc < 3) {
36  printf("Usage: %s <infile.swf> <outfile.swf>\n", argv[0]);
37  return 1;
38  }
39 
40  fd_in = open(argv[1], O_RDONLY);
41  if (fd_in < 0) {
42  perror("Error opening input file");
43  return 1;
44  }
45 
46  fd_out = open(argv[2], O_WRONLY | O_CREAT, 00644);
47  if (fd_out < 0) {
48  perror("Error opening output file");
49  close(fd_in);
50  return 1;
51  }
52 
53  if (read(fd_in, &buf_in, 8) != 8) {
54  printf("Header error\n");
55  close(fd_in);
56  close(fd_out);
57  return 1;
58  }
59 
60  if (buf_in[0] != 'C' || buf_in[1] != 'W' || buf_in[2] != 'S') {
61  printf("Not a compressed flash file\n");
62  return 1;
63  }
64 
65  fstat(fd_in, &statbuf);
66  comp_len = statbuf.st_size;
67  uncomp_len = buf_in[4] | (buf_in[5] << 8) | (buf_in[6] << 16) | (buf_in[7] << 24);
68 
69  printf("Compressed size: %d Uncompressed size: %d\n",
70  comp_len - 4, uncomp_len - 4);
71 
72  // write out modified header
73  buf_in[0] = 'F';
74  if (write(fd_out, &buf_in, 8) < 8) {
75  perror("Error writing output file");
76  return 1;
77  }
78 
79  zstream.zalloc = NULL;
80  zstream.zfree = NULL;
81  zstream.opaque = NULL;
82  inflateInit(&zstream);
83 
84  for (i = 0; i < comp_len - 8;) {
85  int ret, len = read(fd_in, &buf_in, 1024);
86 
87  dbgprintf("read %d bytes\n", len);
88 
89  last_out = zstream.total_out;
90 
91  zstream.next_in = &buf_in[0];
92  zstream.avail_in = len;
93  zstream.next_out = &buf_out[0];
94  zstream.avail_out = 65536;
95 
96  ret = inflate(&zstream, Z_SYNC_FLUSH);
97  if (ret != Z_STREAM_END && ret != Z_OK) {
98  printf("Error while decompressing: %d\n", ret);
99  inflateEnd(&zstream);
100  return 1;
101  }
102 
103  dbgprintf("a_in: %d t_in: %lu a_out: %d t_out: %lu -- %lu out\n",
104  zstream.avail_in, zstream.total_in, zstream.avail_out,
105  zstream.total_out, zstream.total_out - last_out);
106 
107  if (write(fd_out, &buf_out, zstream.total_out - last_out) <
108  zstream.total_out - last_out) {
109  perror("Error writing output file");
110  return 1;
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  return 1;
132  }
133  }
134 
135  inflateEnd(&zstream);
136  close(fd_in);
137  close(fd_out);
138  return 0;
139 }
#define dbgprintf(...)
Definition: cws2fws.c:25
NULL
Definition: eval.c:52
int main(int argc, char *argv[])
Definition: cws2fws.c:28
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:326
int len