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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206
|
#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;
}
int32_t uiff_close(uiff_ctx_t *ctx) {
int ret;
ret = fclose(ctx->f);
free(ctx);
if(ret != 0) return DOS_ERROR;
return IFF_OKAY;
}
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 + 1) & ~1L, 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;
if(ctx->ckend > ctx->grend) {
//Something went wrong! Chunk end is after group end.
size = BAD_IFF;
}
}
ctx->cksz = size;
return size;
}
int32_t uiff_find_chunk_wflags(uiff_ctx_t *ctx, ID ckID, unsigned flags) {
if(flags & IFF_FIND_REWIND) uiff_rewind_group(ctx);
return uiff_find_chunk_ctx(ctx, ckID);
}
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);
}
|