File: u-iff.c

package info (click to toggle)
rockdodger 0.9.2-1
  • links: PTS
  • area: main
  • in suites: jessie, jessie-kfreebsd
  • size: 2,220 kB
  • ctags: 756
  • sloc: ansic: 5,374; makefile: 159; sh: 21
file content (185 lines) | stat: -rw-r--r-- 4,257 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
#include "u-iff.h"
#include <assert.h>
#include <limits.h>
#include <stdlib.h>
#include <string.h>

uiff_ctx_t *uiff_new_ctx(FILE *f, uiff_ctx_t *ctx) {
  if(ctx == NULL) ctx = malloc(sizeof(uiff_ctx_t));
  if(ctx) {
    memset(ctx, 0, sizeof(uiff_ctx_t));
    ctx->f = f;
    //ctx->grbegin = 0;
    ctx->grend = LONG_MAX;
    ctx->grsz = INT32_MAX;
  }
  return ctx;
}

uiff_ctx_t *uiff_from_file(FILE *f, ID grID, ID subID) {
  uiff_ctx_t *ctx;

  ctx = calloc(sizeof(uiff_ctx_t), 1);
  if(ctx) {
    rewind(f);
    uiff_new_ctx(f, ctx);
    if(uiff_find_group_ctx(ctx, 0, grID, subID) >= 0) {
    } else {
      free(ctx);
      return NULL;
    }
  }
  return ctx;
}


uint32_t read32(FILE *inf) {
  uint32_t u32 = 0;
  int c, i;

  for(i = 0; i < 4; ++i) {
    u32 <<= 8;
    c = fgetc(inf);
    //if(c == EOF) return SHORT_CHUNK;
    u32 |= c;
  }
  //if(u32 & 0x80808080) return -8;
  return u32;
}

uint16_t read16(FILE *inf) {
  uint16_t u16;
  int c;

  c = fgetc(inf);
  u16 = c << 8;
  c = fgetc(inf);
  u16 |= c;
  return u16;
}

int32_t uiff_find_chunk(FILE *inf, long length, ID ckID) {
  ID tmpid;
  int32_t size;
  long maxpos;

  maxpos = ftell(inf) + length;
  while(ftell(inf) < maxpos) {
    tmpid = read32(inf);
    if(feof(inf)) return SHORT_CHUNK;
    size = read32(inf);
    if(size < 0) return BAD_FORM;
    if(feof(inf)) return SHORT_CHUNK;
    if(ckID == 0 || tmpid == ckID) {
      return size;
    }
    fseek(inf, size, SEEK_CUR);
  }
  return NOT_IFF;
}

int32_t uiff_find_chunk_ctx(uiff_ctx_t *ctx, ID ckID) {
  int32_t size;
  long pos;

  pos = ftell(ctx->f);
  if(pos < ctx->grbgn || pos > ctx->grend) return CLIENT_ERROR; //fseek(ctx->f, ctx->grbgn, SEEK_SET);
  size = uiff_find_chunk(ctx->f, ctx->grsz, ckID);
  if(size >= 0) {
    pos = ftell(ctx->f);
    ctx->ckID = ckID;
    ctx->ckbgn = pos;
    ctx->ckend = pos + size;
    ctx->cksz = size;
  }
  ctx->cksz = size;
  return size;
}

int32_t uiff_find_group(FILE *inf, long length, ID ckID, ID subID) {
  ID tmpid;
  int32_t size;
  long pos, maxpos;
  int found = 0;

  maxpos = ftell(inf) + length;
  while((pos = ftell(inf)) < maxpos) {
    size = uiff_find_chunk(inf, (maxpos - pos), ckID);
    if(size < 0) return size;
    if(size < 4) return BAD_FORM;
    if(ckID != 0) {
      found = 1;
    } else { //ckID = 0, find any group type
      fseek(inf, -8, SEEK_CUR); //Go back to ID
      tmpid = read32(inf);
      fseek(inf, 4, SEEK_CUR); //Skip size
      if(tmpid == FORM || tmpid == PROP || tmpid == LIST || tmpid == CAT) found = 1;
    }
    if(found) {
      tmpid = read32(inf);
      size -= 4; //Bytes left to read
      if(feof(inf)) return SHORT_CHUNK;
      if(tmpid == subID) {
	return size;
      } else found = 0;
    }
    fseek(inf, size, SEEK_CUR);
  }
  return NOT_IFF;
}

int32_t uiff_find_group_ctx(uiff_ctx_t *ctx, unsigned flags, ID ckID, ID subID) {
  int32_t size;
  long pos;

  if(flags & IFF_FIND_REWIND) uiff_rewind_group(ctx);
  pos = ftell(ctx->f);
  //Am I within a group?
  if(pos < ctx->grbgn || pos > ctx->grend) return CLIENT_ERROR; //fseek(ctx->f, ctx->grbgn, SEEK_SET);
  size = uiff_find_group(ctx->f, ctx->grsz, ckID, subID);
  if(size >= 0) {
    pos = ftell(ctx->f);
    ctx->grID = ckID;
    ctx->grsID = subID;
    ctx->grbgn = pos;
    ctx->grend = pos + size;
    ctx->grsz = size;
    ctx->ckID = 0; //We have no current chunk, set everything to zero/default.
    ctx->ckbgn = 0;
    ctx->ckend = 0;
    ctx->cksz = -1;
  }
  ctx->grsz = size;
  return size;
}

void *uiff_reada_chunk_ctx(uiff_ctx_t *ctx) {
  size_t bytes_read;
  void *ptr = NULL;
  long pos = ftell(ctx->f);

  if(pos >= ctx->grbgn && pos < ctx->grend && ctx->cksz > 0) { //We actually have to read something
    ptr = malloc(ctx->cksz);
    if(ptr) {
      bytes_read = fread(ptr, 1, ctx->cksz, ctx->f);
      if(bytes_read < ctx->cksz) {
	free(ptr);
	return NULL; // This is bad
      }
      ctx->last_data = ptr;
    }
  }
  return ptr;
}

int32_t uiff_skip(uiff_ctx_t *ctx) {
  long pos = ftell(ctx->f);

  if(pos < ctx->ckbgn || pos >= ctx->ckend) return CLIENT_ERROR;
  fseek(ctx->f, ctx->ckend, SEEK_SET);
  return (int32_t)(ctx->ckend - pos);
}

void uiff_rewind_group(uiff_ctx_t *ctx) {
  fseek(ctx->f, ctx->grbgn, SEEK_SET);
}