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Cleanup and better safety checks, 9
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@aaaaaa123456789
aaaaaa123456789 committed Jan 24, 2022
1 parent 60f912a commit e10cee6
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Showing 2 changed files with 46 additions and 77 deletions.
95 changes: 36 additions & 59 deletions src/pngreadframe.c
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Original file line number Diff line number Diff line change
Expand Up @@ -23,7 +23,7 @@ void * load_PNG_frame_part (struct context * context, const size_t * chunks, int
size_t p = 0, total_compressed_size = 0;
const size_t * chunk;
for (chunk = chunks; *chunk; chunk ++) total_compressed_size += read_be32_unaligned(context -> data + *chunk - 8) - chunkoffset;
char * compressed = ctxmalloc(context, total_compressed_size);
unsigned char * compressed = ctxmalloc(context, total_compressed_size);
for (chunk = chunks; *chunk; chunk ++) {
size_t current = read_be32_unaligned(context -> data + *chunk - 8) - chunkoffset;
memcpy(compressed + p, context -> data + *chunk + chunkoffset, current);
Expand Down Expand Up @@ -53,15 +53,15 @@ uint8_t * load_PNG_palette_frame (struct context * context, const void * compres
size_t rowsize, cumulative_size = 0;
uint_fast8_t pass;
for (pass = 0; pass < 7; pass ++) if (widths[pass] && heights[pass]) {
rowsize = ((size_t) widths[pass] * bitdepth + 15) / 8;
rowsize = ((size_t) widths[pass] * bitdepth + 7) / 8 + 1;
cumulative_size += heights[pass] * rowsize;
}
decompressed = decompress_PNG_data(context, compressed, compressed_size, cumulative_size);
unsigned char * current = decompressed;
uint_fast32_t row, col;
size_t row, col;
unsigned char * rowdata = ctxmalloc(context, width);
for (pass = 0; pass < 7; pass ++) if (widths[pass] && heights[pass]) {
rowsize = ((size_t) widths[pass] * bitdepth + 15) / 8;
rowsize = ((size_t) widths[pass] * bitdepth + 7) / 8 + 1;
remove_PNG_filter(context, current, widths[pass], heights[pass], 3, bitdepth);
for (row = 0; row < heights[pass]; row ++) {
expand_bitpacked_PNG_data(rowdata, current + 1, widths[pass], bitdepth);
Expand All @@ -71,7 +71,7 @@ uint8_t * load_PNG_palette_frame (struct context * context, const void * compres
}
ctxfree(context, rowdata);
} else {
size_t row, rowsize = ((size_t) width * bitdepth + 15) / 8;
size_t row, rowsize = ((size_t) width * bitdepth + 7) / 8 + 1;
decompressed = decompress_PNG_data(context, compressed, compressed_size, rowsize * height);
remove_PNG_filter(context, decompressed, width, height, 3, bitdepth);
for (row = 0; row < height; row ++) expand_bitpacked_PNG_data(result + row * width, decompressed + row * rowsize + 1, width, bitdepth);
Expand Down Expand Up @@ -99,19 +99,19 @@ uint64_t * load_PNG_raw_frame (struct context * context, const void * compressed
size_t rowsize, cumulative_size = 0;
uint_fast8_t pass;
for (pass = 0; pass < 7; pass ++) if (widths[pass] && heights[pass]) {
rowsize = pixelsize ? pixelsize * widths[pass] + 1 : (((size_t) widths[pass] * bitdepth + 15) / 8);
rowsize = pixelsize ? pixelsize * widths[pass] + 1 : (((size_t) widths[pass] * bitdepth + 7) / 8 + 1);
cumulative_size += rowsize * heights[pass];
}
decompressed = decompress_PNG_data(context, compressed, compressed_size, cumulative_size);
unsigned char * current = decompressed;
for (pass = 0; pass < 7; pass ++) if (widths[pass] && heights[pass]) {
load_PNG_raw_frame_pass(context, current, result, heights[pass], widths[pass], width, imagetype, bitdepth, coordsH[pass], coordsV[pass],
offsetsH[pass], offsetsV[pass]);
rowsize = pixelsize ? pixelsize * widths[pass] + 1 : (((size_t) widths[pass] * bitdepth + 15) / 8);
rowsize = pixelsize ? pixelsize * widths[pass] + 1 : (((size_t) widths[pass] * bitdepth + 7) / 8 + 1);
current += rowsize * heights[pass];
}
} else {
size_t rowsize = pixelsize ? pixelsize * width + 1 : (((size_t) width * bitdepth + 15) / 8);
size_t rowsize = pixelsize ? pixelsize * width + 1 : (((size_t) width * bitdepth + 7) / 8 + 1);
decompressed = decompress_PNG_data(context, compressed, compressed_size, rowsize * height);
load_PNG_raw_frame_pass(context, decompressed, result, height, width, width, imagetype, bitdepth, 0, 0, 1, 1);
}
Expand All @@ -124,8 +124,8 @@ void load_PNG_raw_frame_pass (struct context * context, unsigned char * restrict
unsigned char offsetV) {
size_t pixelsize = bitdepth / 8; // 0 will be treated as a special value
pixelsize *= (imagetype >> 1)[(unsigned char []) {1, 3, 2, 4}];
size_t rowsize = pixelsize ? pixelsize * width + 1 : (((size_t) width * bitdepth + 15) / 8);
uint_fast32_t row, col;
size_t rowsize = pixelsize ? pixelsize * width + 1 : (((size_t) width * bitdepth + 7) / 8 + 1);
size_t row, col;
remove_PNG_filter(context, data, width, height, imagetype, bitdepth);
unsigned char * rowdata;
uint64_t * rowoutput;
Expand All @@ -134,66 +134,42 @@ void load_PNG_raw_frame_pass (struct context * context, unsigned char * restrict
rowdata = data + 1;
switch (bitdepth + imagetype) {
// since bitdepth must be 8 or 16 here unless imagetype is 0, all combinations are unique
case 8:
for (col = 0; col < width; col ++) rowoutput[col * offsetH + coordH] = (uint64_t) *(rowdata ++) * 0x10101010101u;
case 8: // imagetype = 0, bitdepth = 8
for (col = 0; col < width; col ++) rowoutput[col * offsetH + coordH] = (uint64_t) rowdata[col] * 0x10101010101u;
break;
case 10:
for (col = 0; col < width; col ++) {
uint64_t color = *(rowdata ++);
color |= (uint64_t) *(rowdata ++) << 16;
color |= (uint64_t) *(rowdata ++) << 32;
rowoutput[col * offsetH + coordH] = color * 0x101;
}
case 10: // imagetype = 2, bitdepth = 8
for (col = 0; col < width; col ++)
rowoutput[col * offsetH + coordH] = (rowdata[3 * col] | ((uint64_t) rowdata[3 * col + 1] << 16) | ((uint64_t) rowdata[3 * col + 2] << 32)) * 0x101;
break;
case 12:
for (col = 0; col < width; col ++) {
uint64_t color = (uint64_t) *(rowdata ++) * 0x10101010101u;
color |= (uint64_t) (*(rowdata ++) ^ 0xff) * 0x101000000000000u;
rowoutput[col * offsetH + coordH] = color;
}
case 12: // imagetype = 4, bitdepth = 8
for (col = 0; col < width; col ++)
rowoutput[col * offsetH + coordH] = ((uint64_t) rowdata[2 * col] * 0x10101010101u) | ((uint64_t) (rowdata[2 * col + 1] ^ 0xff) * 0x101000000000000u);
break;
case 14:
for (col = 0; col < width; col ++) {
uint64_t color = *(rowdata ++);
color |= (uint64_t) *(rowdata ++) << 16;
color |= (uint64_t) *(rowdata ++) << 32;
color |= (uint64_t) (*(rowdata ++) ^ 0xff) << 48;
rowoutput[col * offsetH + coordH] = color * 0x101;
}
case 14: // imagetype = 6, bitdepth = 8
for (col = 0; col < width; col ++)
rowoutput[col * offsetH + coordH] = 0x101 * (rowdata[4 * col] | ((uint64_t) rowdata[4 * col + 1] << 16) |
((uint64_t) rowdata[4 * col + 2] << 32) | ((uint64_t) (rowdata[4 * col + 3] ^ 0xff) << 48));
break;
case 16:
case 16: // imagetype = 0, bitdepth = 16
for (col = 0; col < width; col ++) rowoutput[col * offsetH + coordH] = (uint64_t) read_be16_unaligned(rowdata + 2 * col) * 0x100010001u;
break;
case 18:
for (col = 0; col < width; col ++) {
uint64_t color = (uint64_t) *(rowdata ++) << 8;
color |= *(rowdata ++);
color |= (uint64_t) *(rowdata ++) << 24;
color |= (uint64_t) *(rowdata ++) << 16;
color |= (uint64_t) *(rowdata ++) << 40;
color |= (uint64_t) *(rowdata ++) << 32;
rowoutput[col * offsetH + coordH] = color;
}
case 18: // imagetype = 2, bitdepth = 16
for (col = 0; col < width; col ++)
rowoutput[col * offsetH + coordH] = read_be16_unaligned(rowdata + 6 * col) | ((uint64_t) read_be16_unaligned(rowdata + 6 * col + 2) << 16) |
((uint64_t) read_be16_unaligned(rowdata + 6 * col + 4) << 32);
break;
case 20:
case 20: // imagetype = 4, bitdepth = 16
for (col = 0; col < width; col ++)
rowoutput[col * offsetH + coordH] = (uint64_t) read_be16_unaligned(rowdata + 4 * col) * 0x100010001u +
rowoutput[col * offsetH + coordH] = ((uint64_t) read_be16_unaligned(rowdata + 4 * col) * 0x100010001u) |
((uint64_t) ~read_be16_unaligned(rowdata + 4 * col + 2) << 48);
break;
case 22:
for (col = 0; col < width; col ++) {
uint64_t color = (uint64_t) *(rowdata ++) << 8;
color |= *(rowdata ++);
color |= (uint64_t) *(rowdata ++) << 24;
color |= (uint64_t) *(rowdata ++) << 16;
color |= (uint64_t) *(rowdata ++) << 40;
color |= (uint64_t) *(rowdata ++) << 32;
color |= (uint64_t) (*(rowdata ++) ^ 0xff) << 56;
color |= (uint64_t) (*(rowdata ++) ^ 0xff) << 48;
rowoutput[col * offsetH + coordH] = color;
}
case 22: // imagetype = 6, bitdepth = 16
for (col = 0; col < width; col ++)
rowoutput[col * offsetH + coordH] = read_be16_unaligned(rowdata + 8 * col) | ((uint64_t) read_be16_unaligned(rowdata + 8 * col + 2) << 16) |
((uint64_t) read_be16_unaligned(rowdata + 8 * col + 4) << 32) |
((uint64_t) ~read_be16_unaligned(rowdata + 8 * col + 6) << 48);
break;
default: {
default: { // imagetype = 0, bitdepth < 8
unsigned char * buffer = ctxmalloc(context, width);
expand_bitpacked_PNG_data(buffer, rowdata, width, bitdepth);
for (col = 0; col < width; col ++) rowoutput[col * offsetH + coordH] = (uint64_t) bitextend16(buffer[col], bitdepth) * 0x100010001u;
Expand Down Expand Up @@ -248,6 +224,7 @@ void remove_PNG_filter (struct context * context, unsigned char * restrict data,
pixelsize = 1;
width = ((size_t) width * bitdepth + 7) / 8;
}
if (((size_t) pixelsize * width + 1) > PTRDIFF_MAX) throw(context, PLUM_ERR_IMAGE_TOO_LARGE);
ptrdiff_t p, rowsize = pixelsize * width + 1;
uint_fast32_t row;
for (row = 0; row < height; row ++) {
Expand Down
28 changes: 10 additions & 18 deletions src/pngwrite.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -86,7 +86,7 @@ void append_PNG_header_chunks (struct context * context, unsigned type, uint32_t
write_be32_unaligned(header + 4, context -> image -> height);
header[8] = (type < 4) ? 1 << type : (8 << (type >= 6));
header[9] = (type >= 4) ? 2 + 4 * (type & 1) : 3;
header[10] = header[11] = header[12] = 0;
bytewrite(header + 10, 0, 0, 0);
output_PNG_chunk(context, 0x49484452u, sizeof header, header); // IHDR
// reuse the header array for the sBIT chunk
write_le32_unaligned(header, depth); // this will write each byte of depth in the expected position
Expand All @@ -95,7 +95,7 @@ void append_PNG_header_chunks (struct context * context, unsigned type, uint32_t
if (header[1] > 8) header[1] = 8;
if (header[2] > 8) header[2] = 8;
}
output_PNG_chunk(context, 0x73424954u, 3 + ((type == 5) || (type == 7)), header); // sBIT
output_PNG_chunk(context, 0x73424954u, 3 + ((type & 5) == 5), header); // sBIT
}

void append_PNG_palette_data (struct context * context, int use_alpha) {
Expand All @@ -105,16 +105,11 @@ void append_PNG_palette_data (struct context * context, int use_alpha) {
unsigned char data[768];
unsigned char * p = data;
uint_fast16_t index;
for (index = 0; index <= context -> source -> max_palette_index; index ++) {
*(p ++) = color_buffer[index];
*(p ++) = color_buffer[index] >> 8;
*(p ++) = color_buffer[index] >> 16;
}
for (index = 0; index <= context -> source -> max_palette_index; index ++)
p += byteappend(p, color_buffer[index], color_buffer[index] >> 8, color_buffer[index] >> 16);
output_PNG_chunk(context, 0x504c5445u, p - data, data); // PLTE
if (use_alpha) {
p = data;
for (index = 0; index <= context -> source -> max_palette_index; index ++)
*(p ++) = color_buffer[index] >> 24;
for (p = data, index = 0; index <= context -> source -> max_palette_index; index ++) *(p ++) = color_buffer[index] >> 24;
output_PNG_chunk(context, 0x74524e53u, p - data, data); // tRNS
}
}
Expand Down Expand Up @@ -190,8 +185,7 @@ void append_APNG_frame_header (struct context * context, uint64_t duration, uint
memset(data + 12, 0, 8);
write_be16_unaligned(data + 20, numerator);
write_be16_unaligned(data + 22, denominator);
data[24] = disposal % PLUM_DISPOSAL_REPLACE;
data[25] = previous < PLUM_DISPOSAL_REPLACE;
bytewrite(data + 24, disposal % PLUM_DISPOSAL_REPLACE, previous < PLUM_DISPOSAL_REPLACE);
output_PNG_chunk(context, 0x6663544cu, sizeof data, data); // fcTL
}

Expand All @@ -208,14 +202,12 @@ unsigned char * generate_PNG_frame_data (struct context * context, const void *
if (pixelsize)
rowsize = context -> source -> width * pixelsize + 1;
else
rowsize = (((size_t) context -> source -> width << type) + 15) >> 3;
rowsize = (((size_t) context -> source -> width << type) + 7) / 8 + 1;
*size = rowsize * context -> source -> height;
if ((*size > (SIZE_MAX - 2)) || (rowsize > (SIZE_MAX / 6)) || ((*size / rowsize) != context -> source -> height)) throw(context, PLUM_ERR_IMAGE_TOO_LARGE);
// allocate and initialize two extra bytes so the compressor can operate safely
unsigned char * result = ctxmalloc(context, *size + 2);
result[*size] = 0;
result[*size + 1] = 0;
unsigned char * rowbuffer = ctxmalloc(context, 6 * rowsize);
memset(rowbuffer + 5 * rowsize, 0, rowsize);
unsigned char * result = ctxcalloc(context, *size + 2);
unsigned char * rowbuffer = ctxcalloc(context, 6 * rowsize);
uint_fast32_t row;
size_t rowoffset = (type < 4) ? context -> source -> width : plum_color_buffer_size(context -> source -> width, context -> source -> color_format);
for (row = 0; row < context -> source -> height; row ++) {
Expand Down

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