diff options
Diffstat (limited to 'third_party/libpng/pngwutil.c')
| -rw-r--r-- | third_party/libpng/pngwutil.c | 354 |
1 files changed, 178 insertions, 176 deletions
diff --git a/third_party/libpng/pngwutil.c b/third_party/libpng/pngwutil.c index 3f55f57..22a83cc 100644 --- a/third_party/libpng/pngwutil.c +++ b/third_party/libpng/pngwutil.c @@ -1,7 +1,7 @@ /* pngwutil.c - utilities to write a PNG file * - * Last changed in libpng 1.2.36 [May 7, 2009] + * Last changed in libpng 1.2.36 [June 4, 2009] * For conditions of distribution and use, see copyright notice in png.h * Copyright (c) 1998-2009 Glenn Randers-Pehrson * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) @@ -60,7 +60,7 @@ png_write_sig(png_structp png_ptr) { png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10}; - /* write the rest of the 8 byte signature */ + /* Write the rest of the 8 byte signature */ png_write_data(png_ptr, &png_signature[png_ptr->sig_bytes], (png_size_t)(8 - png_ptr->sig_bytes)); if (png_ptr->sig_bytes < 3) @@ -80,7 +80,8 @@ void PNGAPI png_write_chunk(png_structp png_ptr, png_bytep chunk_name, png_bytep data, png_size_t length) { - if (png_ptr == NULL) return; + if (png_ptr == NULL) + return; png_write_chunk_start(png_ptr, chunk_name, (png_uint_32)length); png_write_chunk_data(png_ptr, data, (png_size_t)length); png_write_chunk_end(png_ptr); @@ -98,15 +99,16 @@ png_write_chunk_start(png_structp png_ptr, png_bytep chunk_name, png_debug2(0, "Writing %s chunk, length = %lu", chunk_name, (unsigned long)length); - if (png_ptr == NULL) return; + if (png_ptr == NULL) + return; - /* write the length and the chunk name */ + /* Write the length and the chunk name */ png_save_uint_32(buf, length); png_memcpy(buf + 4, chunk_name, 4); png_write_data(png_ptr, buf, (png_size_t)8); - /* put the chunk name into png_ptr->chunk_name */ + /* Put the chunk name into png_ptr->chunk_name */ png_memcpy(png_ptr->chunk_name, chunk_name, 4); - /* reset the crc and run it over the chunk name */ + /* Reset the crc and run it over the chunk name */ png_reset_crc(png_ptr); png_calculate_crc(png_ptr, chunk_name, (png_size_t)4); } @@ -119,12 +121,13 @@ png_write_chunk_start(png_structp png_ptr, png_bytep chunk_name, void PNGAPI png_write_chunk_data(png_structp png_ptr, png_bytep data, png_size_t length) { - /* write the data, and run the CRC over it */ - if (png_ptr == NULL) return; + /* Write the data, and run the CRC over it */ + if (png_ptr == NULL) + return; if (data != NULL && length > 0) { png_write_data(png_ptr, data, length); - /* update the CRC after writing the data, + /* Update the CRC after writing the data, * in case that the user I/O routine alters it. */ png_calculate_crc(png_ptr, data, length); @@ -139,15 +142,14 @@ png_write_chunk_end(png_structp png_ptr) if (png_ptr == NULL) return; - /* write the crc in a single operation */ + /* Write the crc in a single operation */ png_save_uint_32(buf, png_ptr->crc); png_write_data(png_ptr, buf, (png_size_t)4); } #if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_iCCP_SUPPORTED) -/* - * This pair of functions encapsulates the operation of (a) compressing a +/* This pair of functions encapsulates the operation of (a) compressing a * text string, and (b) issuing it later as a series of chunk data writes. * The compression_state structure is shared context for these functions * set up by the caller in order to make the whole mess thread-safe. @@ -155,14 +157,14 @@ png_write_chunk_end(png_structp png_ptr) typedef struct { - char *input; /* the uncompressed input data */ - int input_len; /* its length */ - int num_output_ptr; /* number of output pointers used */ - int max_output_ptr; /* size of output_ptr */ - png_charpp output_ptr; /* array of pointers to output */ + char *input; /* The uncompressed input data */ + int input_len; /* Its length */ + int num_output_ptr; /* Number of output pointers used */ + int max_output_ptr; /* Size of output_ptr */ + png_charpp output_ptr; /* Array of pointers to output */ } compression_state; -/* compress given text into storage in the png_ptr structure */ +/* Compress given text into storage in the png_ptr structure */ static int /* PRIVATE */ png_text_compress(png_structp png_ptr, png_charp text, png_size_t text_len, int compression, @@ -176,7 +178,7 @@ png_text_compress(png_structp png_ptr, comp->input = NULL; comp->input_len = 0; - /* we may just want to pass the text right through */ + /* We may just want to pass the text right through */ if (compression == PNG_TEXT_COMPRESSION_NONE) { comp->input = text; @@ -210,29 +212,29 @@ png_text_compress(png_structp png_ptr, * wouldn't cause a failure, just a slowdown due to swapping). */ - /* set up the compression buffers */ + /* Set up the compression buffers */ png_ptr->zstream.avail_in = (uInt)text_len; png_ptr->zstream.next_in = (Bytef *)text; png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; png_ptr->zstream.next_out = (Bytef *)png_ptr->zbuf; - /* this is the same compression loop as in png_write_row() */ + /* This is the same compression loop as in png_write_row() */ do { - /* compress the data */ + /* Compress the data */ ret = deflate(&png_ptr->zstream, Z_NO_FLUSH); if (ret != Z_OK) { - /* error */ + /* Error */ if (png_ptr->zstream.msg != NULL) png_error(png_ptr, png_ptr->zstream.msg); else png_error(png_ptr, "zlib error"); } - /* check to see if we need more room */ + /* Check to see if we need more room */ if (!(png_ptr->zstream.avail_out)) { - /* make sure the output array has room */ + /* Make sure the output array has room */ if (comp->num_output_ptr >= comp->max_output_ptr) { int old_max; @@ -257,7 +259,7 @@ png_text_compress(png_structp png_ptr, (comp->max_output_ptr * png_sizeof(png_charp))); } - /* save the data */ + /* Save the data */ comp->output_ptr[comp->num_output_ptr] = (png_charp)png_malloc(png_ptr, (png_uint_32)png_ptr->zbuf_size); @@ -269,21 +271,21 @@ png_text_compress(png_structp png_ptr, png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; png_ptr->zstream.next_out = png_ptr->zbuf; } - /* continue until we don't have any more to compress */ + /* Continue until we don't have any more to compress */ } while (png_ptr->zstream.avail_in); - /* finish the compression */ + /* Finish the compression */ do { - /* tell zlib we are finished */ + /* Tell zlib we are finished */ ret = deflate(&png_ptr->zstream, Z_FINISH); if (ret == Z_OK) { - /* check to see if we need more room */ + /* Check to see if we need more room */ if (!(png_ptr->zstream.avail_out)) { - /* check to make sure our output array has room */ + /* Check to make sure our output array has room */ if (comp->num_output_ptr >= comp->max_output_ptr) { int old_max; @@ -309,7 +311,7 @@ png_text_compress(png_structp png_ptr, png_sizeof(png_charp))); } - /* save off the data */ + /* Save the data */ comp->output_ptr[comp->num_output_ptr] = (png_charp)png_malloc(png_ptr, (png_uint_32)png_ptr->zbuf_size); @@ -324,7 +326,7 @@ png_text_compress(png_structp png_ptr, } else if (ret != Z_STREAM_END) { - /* we got an error */ + /* We got an error */ if (png_ptr->zstream.msg != NULL) png_error(png_ptr, png_ptr->zstream.msg); else @@ -332,7 +334,7 @@ png_text_compress(png_structp png_ptr, } } while (ret != Z_STREAM_END); - /* text length is number of buffers plus last buffer */ + /* Text length is number of buffers plus last buffer */ text_len = png_ptr->zbuf_size * comp->num_output_ptr; if (png_ptr->zstream.avail_out < png_ptr->zbuf_size) text_len += png_ptr->zbuf_size - (png_size_t)png_ptr->zstream.avail_out; @@ -340,21 +342,21 @@ png_text_compress(png_structp png_ptr, return((int)text_len); } -/* ship the compressed text out via chunk writes */ +/* Ship the compressed text out via chunk writes */ static void /* PRIVATE */ png_write_compressed_data_out(png_structp png_ptr, compression_state *comp) { int i; - /* handle the no-compression case */ + /* Handle the no-compression case */ if (comp->input) { - png_write_chunk_data(png_ptr, (png_bytep)comp->input, + png_write_chunk_data(png_ptr, (png_bytep)comp->input, (png_size_t)comp->input_len); - return; + return; } - /* write saved output buffers, if any */ + /* Write saved output buffers, if any */ for (i = 0; i < comp->num_output_ptr; i++) { png_write_chunk_data(png_ptr, (png_bytep)comp->output_ptr[i], @@ -365,12 +367,12 @@ png_write_compressed_data_out(png_structp png_ptr, compression_state *comp) if (comp->max_output_ptr != 0) png_free(png_ptr, comp->output_ptr); comp->output_ptr=NULL; - /* write anything left in zbuf */ + /* Write anything left in zbuf */ if (png_ptr->zstream.avail_out < (png_uint_32)png_ptr->zbuf_size) png_write_chunk_data(png_ptr, png_ptr->zbuf, (png_size_t)(png_ptr->zbuf_size - png_ptr->zstream.avail_out)); - /* reset zlib for another zTXt/iTXt or image data */ + /* Reset zlib for another zTXt/iTXt or image data */ deflateReset(&png_ptr->zstream); png_ptr->zstream.data_type = Z_BINARY; } @@ -390,7 +392,7 @@ png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height, #endif int ret; - png_byte buf[13]; /* buffer to store the IHDR info */ + png_byte buf[13]; /* Buffer to store the IHDR info */ png_debug(1, "in png_write_IHDR"); /* Check that we have valid input data from the application info */ @@ -476,7 +478,7 @@ png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height, interlace_type=PNG_INTERLACE_NONE; #endif - /* save off the relevent information */ + /* Save the relevent information */ png_ptr->bit_depth = (png_byte)bit_depth; png_ptr->color_type = (png_byte)color_type; png_ptr->interlaced = (png_byte)interlace_type; @@ -489,12 +491,12 @@ png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height, png_ptr->pixel_depth = (png_byte)(bit_depth * png_ptr->channels); png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth, width); - /* set the usr info, so any transformations can modify it */ + /* Set the usr info, so any transformations can modify it */ png_ptr->usr_width = png_ptr->width; png_ptr->usr_bit_depth = png_ptr->bit_depth; png_ptr->usr_channels = png_ptr->channels; - /* pack the header information into the buffer */ + /* Pack the header information into the buffer */ png_save_uint_32(buf, width); png_save_uint_32(buf + 4, height); buf[8] = (png_byte)bit_depth; @@ -503,10 +505,10 @@ png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height, buf[11] = (png_byte)filter_type; buf[12] = (png_byte)interlace_type; - /* write the chunk */ + /* Write the chunk */ png_write_chunk(png_ptr, (png_bytep)png_IHDR, buf, (png_size_t)13); - /* initialize zlib with PNG info */ + /* Initialize zlib with PNG info */ png_ptr->zstream.zalloc = png_zalloc; png_ptr->zstream.zfree = png_zfree; png_ptr->zstream.opaque = (voidpf)png_ptr; @@ -549,13 +551,13 @@ png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height, png_ptr->zstream.next_out = png_ptr->zbuf; png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; /* libpng is not interested in zstream.data_type */ - /* set it to a predefined value, to avoid its evaluation inside zlib */ + /* Set it to a predefined value, to avoid its evaluation inside zlib */ png_ptr->zstream.data_type = Z_BINARY; png_ptr->mode = PNG_HAVE_IHDR; } -/* write the palette. We are careful not to trust png_color to be in the +/* Write the palette. We are careful not to trust png_color to be in the * correct order for PNG, so people can redefine it to any convenient * structure. */ @@ -622,7 +624,7 @@ png_write_PLTE(png_structp png_ptr, png_colorp palette, png_uint_32 num_pal) png_ptr->mode |= PNG_HAVE_PLTE; } -/* write an IDAT chunk */ +/* Write an IDAT chunk */ void /* PRIVATE */ png_write_IDAT(png_structp png_ptr, png_bytep data, png_size_t length) { @@ -639,9 +641,11 @@ png_write_IDAT(png_structp png_ptr, png_bytep data, png_size_t length) unsigned int z_cmf = data[0]; /* zlib compression method and flags */ if ((z_cmf & 0x0f) == 8 && (z_cmf & 0xf0) <= 0x70) { - /* Avoid memory underflows and multiplication overflows. */ - /* The conditions below are practically always satisfied; - however, they still must be checked. */ + /* Avoid memory underflows and multiplication overflows. + * + * The conditions below are practically always satisfied; + * however, they still must be checked. + */ if (length >= 2 && png_ptr->height < 16384 && png_ptr->width < 16384) { @@ -674,7 +678,7 @@ png_write_IDAT(png_structp png_ptr, png_bytep data, png_size_t length) png_ptr->mode |= PNG_HAVE_IDAT; } -/* write an IEND chunk */ +/* Write an IEND chunk */ void /* PRIVATE */ png_write_IEND(png_structp png_ptr) { @@ -688,7 +692,7 @@ png_write_IEND(png_structp png_ptr) } #if defined(PNG_WRITE_gAMA_SUPPORTED) -/* write a gAMA chunk */ +/* Write a gAMA chunk */ #ifdef PNG_FLOATING_POINT_SUPPORTED void /* PRIVATE */ png_write_gAMA(png_structp png_ptr, double file_gamma) @@ -724,7 +728,7 @@ png_write_gAMA_fixed(png_structp png_ptr, png_fixed_point file_gamma) #endif #if defined(PNG_WRITE_sRGB_SUPPORTED) -/* write a sRGB chunk */ +/* Write a sRGB chunk */ void /* PRIVATE */ png_write_sRGB(png_structp png_ptr, int srgb_intent) { @@ -743,7 +747,7 @@ png_write_sRGB(png_structp png_ptr, int srgb_intent) #endif #if defined(PNG_WRITE_iCCP_SUPPORTED) -/* write an iCCP chunk */ +/* Write an iCCP chunk */ void /* PRIVATE */ png_write_iCCP(png_structp png_ptr, png_charp name, int compression_type, png_charp profile, int profile_len) @@ -800,7 +804,7 @@ png_write_iCCP(png_structp png_ptr, png_charp name, int compression_type, profile_len = png_text_compress(png_ptr, profile, (png_size_t)profile_len, PNG_COMPRESSION_TYPE_BASE, &comp); - /* make sure we include the NULL after the name and the compression type */ + /* Make sure we include the NULL after the name and the compression type */ png_write_chunk_start(png_ptr, (png_bytep)png_iCCP, (png_uint_32)(name_len + profile_len + 2)); new_name[name_len + 1] = 0x00; @@ -816,7 +820,7 @@ png_write_iCCP(png_structp png_ptr, png_charp name, int compression_type, #endif #if defined(PNG_WRITE_sPLT_SUPPORTED) -/* write a sPLT chunk */ +/* Write a sPLT chunk */ void /* PRIVATE */ png_write_sPLT(png_structp png_ptr, png_sPLT_tp spalette) { @@ -834,18 +838,17 @@ png_write_sPLT(png_structp png_ptr, png_sPLT_tp spalette) #endif png_debug(1, "in png_write_sPLT"); - if ((name_len = png_check_keyword(png_ptr, - spalette->name, &new_name))==0) - return; + if ((name_len = png_check_keyword(png_ptr,spalette->name, &new_name))==0) + return; - /* make sure we include the NULL after the name */ + /* Make sure we include the NULL after the name */ png_write_chunk_start(png_ptr, (png_bytep)png_sPLT, (png_uint_32)(name_len + 2 + palette_size)); png_write_chunk_data(png_ptr, (png_bytep)new_name, (png_size_t)(name_len + 1)); png_write_chunk_data(png_ptr, (png_bytep)&spalette->depth, (png_size_t)1); - /* loop through each palette entry, writing appropriately */ + /* Loop through each palette entry, writing appropriately */ #ifndef PNG_NO_POINTER_INDEXING for (ep = spalette->entries; ep<spalette->entries + spalette->nentries; ep++) { @@ -897,7 +900,7 @@ png_write_sPLT(png_structp png_ptr, png_sPLT_tp spalette) #endif #if defined(PNG_WRITE_sBIT_SUPPORTED) -/* write the sBIT chunk */ +/* Write the sBIT chunk */ void /* PRIVATE */ png_write_sBIT(png_structp png_ptr, png_color_8p sbit, int color_type) { @@ -908,7 +911,7 @@ png_write_sBIT(png_structp png_ptr, png_color_8p sbit, int color_type) png_size_t size; png_debug(1, "in png_write_sBIT"); - /* make sure we don't depend upon the order of PNG_COLOR_8 */ + /* Make sure we don't depend upon the order of PNG_COLOR_8 */ if (color_type & PNG_COLOR_MASK_COLOR) { png_byte maxbits; @@ -953,7 +956,7 @@ png_write_sBIT(png_structp png_ptr, png_color_8p sbit, int color_type) #endif #if defined(PNG_WRITE_cHRM_SUPPORTED) -/* write the cHRM chunk */ +/* Write the cHRM chunk */ #ifdef PNG_FLOATING_POINT_SUPPORTED void /* PRIVATE */ png_write_cHRM(png_structp png_ptr, double white_x, double white_y, @@ -984,21 +987,21 @@ png_write_cHRM(png_structp png_ptr, double white_x, double white_y, int_red_x, int_red_y, int_green_x, int_green_y, int_blue_x, int_blue_y)) #endif { - /* each value is saved in 1/100,000ths */ - - png_save_uint_32(buf, int_white_x); - png_save_uint_32(buf + 4, int_white_y); + /* Each value is saved in 1/100,000ths */ + + png_save_uint_32(buf, int_white_x); + png_save_uint_32(buf + 4, int_white_y); - png_save_uint_32(buf + 8, int_red_x); - png_save_uint_32(buf + 12, int_red_y); + png_save_uint_32(buf + 8, int_red_x); + png_save_uint_32(buf + 12, int_red_y); - png_save_uint_32(buf + 16, int_green_x); - png_save_uint_32(buf + 20, int_green_y); + png_save_uint_32(buf + 16, int_green_x); + png_save_uint_32(buf + 20, int_green_y); - png_save_uint_32(buf + 24, int_blue_x); - png_save_uint_32(buf + 28, int_blue_y); + png_save_uint_32(buf + 24, int_blue_x); + png_save_uint_32(buf + 28, int_blue_y); - png_write_chunk(png_ptr, (png_bytep)png_cHRM, buf, (png_size_t)32); + png_write_chunk(png_ptr, (png_bytep)png_cHRM, buf, (png_size_t)32); } } #endif @@ -1015,32 +1018,32 @@ png_write_cHRM_fixed(png_structp png_ptr, png_fixed_point white_x, png_byte buf[32]; png_debug(1, "in png_write_cHRM"); - /* each value is saved in 1/100,000ths */ + /* Each value is saved in 1/100,000ths */ #if !defined(PNG_NO_CHECK_cHRM) if (png_check_cHRM_fixed(png_ptr, white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y)) #endif { - png_save_uint_32(buf, (png_uint_32)white_x); - png_save_uint_32(buf + 4, (png_uint_32)white_y); + png_save_uint_32(buf, (png_uint_32)white_x); + png_save_uint_32(buf + 4, (png_uint_32)white_y); - png_save_uint_32(buf + 8, (png_uint_32)red_x); - png_save_uint_32(buf + 12, (png_uint_32)red_y); + png_save_uint_32(buf + 8, (png_uint_32)red_x); + png_save_uint_32(buf + 12, (png_uint_32)red_y); - png_save_uint_32(buf + 16, (png_uint_32)green_x); - png_save_uint_32(buf + 20, (png_uint_32)green_y); + png_save_uint_32(buf + 16, (png_uint_32)green_x); + png_save_uint_32(buf + 20, (png_uint_32)green_y); - png_save_uint_32(buf + 24, (png_uint_32)blue_x); - png_save_uint_32(buf + 28, (png_uint_32)blue_y); + png_save_uint_32(buf + 24, (png_uint_32)blue_x); + png_save_uint_32(buf + 28, (png_uint_32)blue_y); - png_write_chunk(png_ptr, (png_bytep)png_cHRM, buf, (png_size_t)32); + png_write_chunk(png_ptr, (png_bytep)png_cHRM, buf, (png_size_t)32); } } #endif #endif #if defined(PNG_WRITE_tRNS_SUPPORTED) -/* write the tRNS chunk */ +/* Write the tRNS chunk */ void /* PRIVATE */ png_write_tRNS(png_structp png_ptr, png_bytep trans, png_color_16p tran, int num_trans, int color_type) @@ -1058,13 +1061,13 @@ png_write_tRNS(png_structp png_ptr, png_bytep trans, png_color_16p tran, png_warning(png_ptr, "Invalid number of transparent colors specified"); return; } - /* write the chunk out as it is */ + /* Write the chunk out as it is */ png_write_chunk(png_ptr, (png_bytep)png_tRNS, trans, (png_size_t)num_trans); } else if (color_type == PNG_COLOR_TYPE_GRAY) { - /* one 16 bit value */ + /* One 16 bit value */ if (tran->gray >= (1 << png_ptr->bit_depth)) { png_warning(png_ptr, @@ -1076,7 +1079,7 @@ png_write_tRNS(png_structp png_ptr, png_bytep trans, png_color_16p tran, } else if (color_type == PNG_COLOR_TYPE_RGB) { - /* three 16 bit values */ + /* Three 16 bit values */ png_save_uint_16(buf, tran->red); png_save_uint_16(buf + 2, tran->green); png_save_uint_16(buf + 4, tran->blue); @@ -1096,7 +1099,7 @@ png_write_tRNS(png_structp png_ptr, png_bytep trans, png_color_16p tran, #endif #if defined(PNG_WRITE_bKGD_SUPPORTED) -/* write the background chunk */ +/* Write the background chunk */ void /* PRIVATE */ png_write_bKGD(png_structp png_ptr, png_color_16p back, int color_type) { @@ -1149,7 +1152,7 @@ png_write_bKGD(png_structp png_ptr, png_color_16p back, int color_type) #endif #if defined(PNG_WRITE_hIST_SUPPORTED) -/* write the histogram */ +/* Write the histogram */ void /* PRIVATE */ png_write_hIST(png_structp png_ptr, png_uint_16p hist, int num_hist) { @@ -1249,8 +1252,8 @@ png_check_keyword(png_structp png_ptr, png_charp key, png_charpp new_key) while (*kp == ' ') { - *(kp--) = '\0'; - key_len--; + *(kp--) = '\0'; + key_len--; } } @@ -1262,8 +1265,8 @@ png_check_keyword(png_structp png_ptr, png_charp key, png_charpp new_key) while (*kp == ' ') { - kp++; - key_len--; + kp++; + key_len--; } } @@ -1311,7 +1314,7 @@ png_check_keyword(png_structp png_ptr, png_charp key, png_charpp new_key) #endif #if defined(PNG_WRITE_tEXt_SUPPORTED) -/* write a tEXt chunk */ +/* Write a tEXt chunk */ void /* PRIVATE */ png_write_tEXt(png_structp png_ptr, png_charp key, png_charp text, png_size_t text_len) @@ -1331,7 +1334,7 @@ png_write_tEXt(png_structp png_ptr, png_charp key, png_charp text, else text_len = png_strlen(text); - /* make sure we include the 0 after the key */ + /* Make sure we include the 0 after the key */ png_write_chunk_start(png_ptr, (png_bytep)png_tEXt, (png_uint_32)(key_len + text_len + 1)); /* @@ -1351,7 +1354,7 @@ png_write_tEXt(png_structp png_ptr, png_charp key, png_charp text, #endif #if defined(PNG_WRITE_zTXt_SUPPORTED) -/* write a compressed text chunk */ +/* Write a compressed text chunk */ void /* PRIVATE */ png_write_zTXt(png_structp png_ptr, png_charp key, png_charp text, png_size_t text_len, int compression) @@ -1387,31 +1390,31 @@ png_write_zTXt(png_structp png_ptr, png_charp key, png_charp text, text_len = png_strlen(text); - /* compute the compressed data; do it now for the length */ + /* Compute the compressed data; do it now for the length */ text_len = png_text_compress(png_ptr, text, text_len, compression, &comp); - /* write start of chunk */ + /* Write start of chunk */ png_write_chunk_start(png_ptr, (png_bytep)png_zTXt, (png_uint_32)(key_len+text_len + 2)); - /* write key */ + /* Write key */ png_write_chunk_data(png_ptr, (png_bytep)new_key, (png_size_t)(key_len + 1)); png_free(png_ptr, new_key); buf[0] = (png_byte)compression; - /* write compression */ + /* Write compression */ png_write_chunk_data(png_ptr, (png_bytep)buf, (png_size_t)1); - /* write the compressed data */ + /* Write the compressed data */ png_write_compressed_data_out(png_ptr, &comp); - /* close the chunk */ + /* Close the chunk */ png_write_chunk_end(png_ptr); } #endif #if defined(PNG_WRITE_iTXt_SUPPORTED) -/* write an iTXt chunk */ +/* Write an iTXt chunk */ void /* PRIVATE */ png_write_iTXt(png_structp png_ptr, int compression, png_charp key, png_charp lang, png_charp lang_key, png_charp text) @@ -1443,21 +1446,21 @@ png_write_iTXt(png_structp png_ptr, int compression, png_charp key, } if (lang_key == NULL) - lang_key_len = 0; + lang_key_len = 0; else - lang_key_len = png_strlen(lang_key); + lang_key_len = png_strlen(lang_key); if (text == NULL) text_len = 0; else - text_len = png_strlen(text); + text_len = png_strlen(text); - /* compute the compressed data; do it now for the length */ + /* Compute the compressed data; do it now for the length */ text_len = png_text_compress(png_ptr, text, text_len, compression-2, &comp); - /* make sure we include the compression flag, the compression byte, + /* Make sure we include the compression flag, the compression byte, * and the NULs after the key, lang, and lang_key parts */ png_write_chunk_start(png_ptr, (png_bytep)png_iTXt, @@ -1468,8 +1471,7 @@ png_write_iTXt(png_structp png_ptr, int compression, png_charp key, + lang_key_len + text_len)); - /* - * We leave it to the application to meet PNG-1.0 requirements on the + /* We leave it to the application to meet PNG-1.0 requirements on the * contents of the text. PNG-1.0 through PNG-1.2 discourage the use of * any non-Latin-1 characters except for NEWLINE. ISO PNG will forbid them. * The NUL character is forbidden by PNG-1.0 through PNG-1.2 and ISO PNG. @@ -1477,13 +1479,13 @@ png_write_iTXt(png_structp png_ptr, int compression, png_charp key, png_write_chunk_data(png_ptr, (png_bytep)new_key, (png_size_t)(key_len + 1)); - /* set the compression flag */ + /* Set the compression flag */ if (compression == PNG_ITXT_COMPRESSION_NONE || \ compression == PNG_TEXT_COMPRESSION_NONE) cbuf[0] = 0; else /* compression == PNG_ITXT_COMPRESSION_zTXt */ cbuf[0] = 1; - /* set the compression method */ + /* Set the compression method */ cbuf[1] = 0; png_write_chunk_data(png_ptr, cbuf, (png_size_t)2); @@ -1501,7 +1503,7 @@ png_write_iTXt(png_structp png_ptr, int compression, png_charp key, #endif #if defined(PNG_WRITE_oFFs_SUPPORTED) -/* write the oFFs chunk */ +/* Write the oFFs chunk */ void /* PRIVATE */ png_write_oFFs(png_structp png_ptr, png_int_32 x_offset, png_int_32 y_offset, int unit_type) @@ -1523,7 +1525,7 @@ png_write_oFFs(png_structp png_ptr, png_int_32 x_offset, png_int_32 y_offset, } #endif #if defined(PNG_WRITE_pCAL_SUPPORTED) -/* write the pCAL chunk (described in the PNG extensions document) */ +/* Write the pCAL chunk (described in the PNG extensions document) */ void /* PRIVATE */ png_write_pCAL(png_structp png_ptr, png_charp purpose, png_int_32 X0, png_int_32 X1, int type, int nparams, png_charp units, png_charpp params) @@ -1585,7 +1587,7 @@ png_write_pCAL(png_structp png_ptr, png_charp purpose, png_int_32 X0, #endif #if defined(PNG_WRITE_sCAL_SUPPORTED) -/* write the sCAL chunk */ +/* Write the sCAL chunk */ #if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO) void /* PRIVATE */ png_write_sCAL(png_structp png_ptr, int unit, double width, double height) @@ -1648,8 +1650,8 @@ png_write_sCAL_s(png_structp png_ptr, int unit, png_charp width, } buf[0] = (png_byte)unit; - png_memcpy(buf + 1, width, wlen + 1); /* append the '\0' here */ - png_memcpy(buf + wlen + 2, height, hlen); /* do NOT append the '\0' here */ + png_memcpy(buf + 1, width, wlen + 1); /* Append the '\0' here */ + png_memcpy(buf + wlen + 2, height, hlen); /* Do NOT append the '\0' here */ png_debug1(3, "sCAL total length = %u", (unsigned int)total_len); png_write_chunk(png_ptr, (png_bytep)png_sCAL, buf, total_len); @@ -1659,7 +1661,7 @@ png_write_sCAL_s(png_structp png_ptr, int unit, png_charp width, #endif #if defined(PNG_WRITE_pHYs_SUPPORTED) -/* write the pHYs chunk */ +/* Write the pHYs chunk */ void /* PRIVATE */ png_write_pHYs(png_structp png_ptr, png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit, @@ -1714,24 +1716,24 @@ png_write_tIME(png_structp png_ptr, png_timep mod_time) } #endif -/* initializes the row writing capability of libpng */ +/* Initializes the row writing capability of libpng */ void /* PRIVATE */ png_write_start_row(png_structp png_ptr) { #ifdef PNG_WRITE_INTERLACING_SUPPORTED #ifdef PNG_USE_LOCAL_ARRAYS - /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */ + /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */ - /* start of interlace block */ + /* Start of interlace block */ int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0}; - /* offset to next interlace block */ + /* Offset to next interlace block */ int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; - /* start of interlace block in the y direction */ + /* Start of interlace block in the y direction */ int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1}; - /* offset to next interlace block in the y direction */ + /* Offset to next interlace block in the y direction */ int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2}; #endif #endif @@ -1742,13 +1744,13 @@ png_write_start_row(png_structp png_ptr) buf_size = (png_size_t)(PNG_ROWBYTES( png_ptr->usr_channels*png_ptr->usr_bit_depth, png_ptr->width) + 1); - /* set up row buffer */ + /* Set up row buffer */ png_ptr->row_buf = (png_bytep)png_malloc(png_ptr, (png_uint_32)buf_size); png_ptr->row_buf[0] = PNG_FILTER_VALUE_NONE; #ifndef PNG_NO_WRITE_FILTER - /* set up filtering buffer, if using this filter */ + /* Set up filtering buffer, if using this filter */ if (png_ptr->do_filter & PNG_FILTER_SUB) { png_ptr->sub_row = (png_bytep)png_malloc(png_ptr, @@ -1759,7 +1761,7 @@ png_write_start_row(png_structp png_ptr) /* We only need to keep the previous row if we are using one of these. */ if (png_ptr->do_filter & (PNG_FILTER_AVG | PNG_FILTER_UP | PNG_FILTER_PAETH)) { - /* set up previous row buffer */ + /* Set up previous row buffer */ png_ptr->prev_row = (png_bytep)png_malloc(png_ptr, (png_uint_32)buf_size); png_memset(png_ptr->prev_row, 0, buf_size); @@ -1788,7 +1790,7 @@ png_write_start_row(png_structp png_ptr) #endif /* PNG_NO_WRITE_FILTER */ #ifdef PNG_WRITE_INTERLACING_SUPPORTED - /* if interlaced, we need to set up width and height of pass */ + /* If interlaced, we need to set up width and height of pass */ if (png_ptr->interlaced) { if (!(png_ptr->transformations & PNG_INTERLACE)) @@ -1820,18 +1822,18 @@ png_write_finish_row(png_structp png_ptr) { #ifdef PNG_WRITE_INTERLACING_SUPPORTED #ifdef PNG_USE_LOCAL_ARRAYS - /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */ + /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */ - /* start of interlace block */ + /* Start of interlace block */ int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0}; - /* offset to next interlace block */ + /* Offset to next interlace block */ int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; - /* start of interlace block in the y direction */ + /* Start of interlace block in the y direction */ int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1}; - /* offset to next interlace block in the y direction */ + /* Offset to next interlace block in the y direction */ int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2}; #endif #endif @@ -1839,15 +1841,15 @@ png_write_finish_row(png_structp png_ptr) int ret; png_debug(1, "in png_write_finish_row"); - /* next row */ + /* Next row */ png_ptr->row_number++; - /* see if we are done */ + /* See if we are done */ if (png_ptr->row_number < png_ptr->num_rows) return; #ifdef PNG_WRITE_INTERLACING_SUPPORTED - /* if interlaced, go to next pass */ + /* If interlaced, go to next pass */ if (png_ptr->interlaced) { png_ptr->row_number = 0; @@ -1857,7 +1859,7 @@ png_write_finish_row(png_structp png_ptr) } else { - /* loop until we find a non-zero width or height pass */ + /* Loop until we find a non-zero width or height pass */ do { png_ptr->pass++; @@ -1877,7 +1879,7 @@ png_write_finish_row(png_structp png_ptr) } - /* reset the row above the image for the next pass */ + /* Reset the row above the image for the next pass */ if (png_ptr->pass < 7) { if (png_ptr->prev_row != NULL) @@ -1889,16 +1891,16 @@ png_write_finish_row(png_structp png_ptr) } #endif - /* if we get here, we've just written the last row, so we need + /* If we get here, we've just written the last row, so we need to flush the compressor */ do { - /* tell the compressor we are done */ + /* Tell the compressor we are done */ ret = deflate(&png_ptr->zstream, Z_FINISH); - /* check for an error */ + /* Check for an error */ if (ret == Z_OK) { - /* check to see if we need more room */ + /* Check to see if we need more room */ if (!(png_ptr->zstream.avail_out)) { png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size); @@ -1915,7 +1917,7 @@ png_write_finish_row(png_structp png_ptr) } } while (ret != Z_STREAM_END); - /* write any extra space */ + /* Write any extra space */ if (png_ptr->zstream.avail_out < png_ptr->zbuf_size) { png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size - @@ -1938,24 +1940,24 @@ void /* PRIVATE */ png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass) { #ifdef PNG_USE_LOCAL_ARRAYS - /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */ + /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */ - /* start of interlace block */ + /* Start of interlace block */ int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0}; - /* offset to next interlace block */ + /* Offset to next interlace block */ int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; #endif png_debug(1, "in png_do_write_interlace"); - /* we don't have to do anything on the last pass (6) */ + /* We don't have to do anything on the last pass (6) */ #if defined(PNG_USELESS_TESTS_SUPPORTED) if (row != NULL && row_info != NULL && pass < 6) #else if (pass < 6) #endif { - /* each pixel depth is handled separately */ + /* Each pixel depth is handled separately */ switch (row_info->pixel_depth) { case 1: @@ -2066,27 +2068,27 @@ png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass) png_uint_32 row_width = row_info->width; png_size_t pixel_bytes; - /* start at the beginning */ + /* Start at the beginning */ dp = row; - /* find out how many bytes each pixel takes up */ + /* Find out how many bytes each pixel takes up */ pixel_bytes = (row_info->pixel_depth >> 3); - /* loop through the row, only looking at the pixels that + /* Loop through the row, only looking at the pixels that matter */ for (i = png_pass_start[pass]; i < row_width; i += png_pass_inc[pass]) { - /* find out where the original pixel is */ + /* Find out where the original pixel is */ sp = row + (png_size_t)i * pixel_bytes; - /* move the pixel */ + /* Move the pixel */ if (dp != sp) png_memcpy(dp, sp, pixel_bytes); - /* next pixel */ + /* Next pixel */ dp += pixel_bytes; } break; } } - /* set new row width */ + /* Set new row width */ row_info->width = (row_info->width + png_pass_inc[pass] - 1 - png_pass_start[pass]) / @@ -2119,7 +2121,7 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info) #endif png_debug(1, "in png_write_find_filter"); - /* find out how many bytes offset each pixel is */ + /* Find out how many bytes offset each pixel is */ bpp = (row_info->pixel_depth + 7) >> 3; prev_row = png_ptr->prev_row; @@ -2206,9 +2208,9 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info) mins = sum; } - /* sub filter */ + /* Sub filter */ if (filter_to_do == PNG_FILTER_SUB) - /* it's the only filter so no testing is needed */ + /* It's the only filter so no testing is needed */ { png_bytep rp, lp, dp; png_uint_32 i; @@ -2323,7 +2325,7 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info) } } - /* up filter */ + /* Up filter */ if (filter_to_do == PNG_FILTER_UP) { png_bytep rp, dp, pp; @@ -2426,7 +2428,7 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info) } } - /* avg filter */ + /* Avg filter */ if (filter_to_do == PNG_FILTER_AVG) { png_bytep rp, dp, pp, lp; @@ -2729,18 +2731,18 @@ png_write_filtered_row(png_structp png_ptr, png_bytep filtered_row) { png_debug(1, "in png_write_filtered_row"); png_debug1(2, "filter = %d", filtered_row[0]); - /* set up the zlib input buffer */ + /* Set up the zlib input buffer */ png_ptr->zstream.next_in = filtered_row; png_ptr->zstream.avail_in = (uInt)png_ptr->row_info.rowbytes + 1; - /* repeat until we have compressed all the data */ + /* Repeat until we have compressed all the data */ do { - int ret; /* return of zlib */ + int ret; /* Return of zlib */ - /* compress the data */ + /* Compress the data */ ret = deflate(&png_ptr->zstream, Z_NO_FLUSH); - /* check for compression errors */ + /* Check for compression errors */ if (ret != Z_OK) { if (png_ptr->zstream.msg != NULL) @@ -2749,18 +2751,18 @@ png_write_filtered_row(png_structp png_ptr, png_bytep filtered_row) png_error(png_ptr, "zlib error"); } - /* see if it is time to write another IDAT */ + /* See if it is time to write another IDAT */ if (!(png_ptr->zstream.avail_out)) { - /* write the IDAT and reset the zlib output buffer */ + /* Write the IDAT and reset the zlib output buffer */ png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size); png_ptr->zstream.next_out = png_ptr->zbuf; png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; } - /* repeat until all data has been compressed */ + /* Repeat until all data has been compressed */ } while (png_ptr->zstream.avail_in); - /* swap the current and previous rows */ + /* Swap the current and previous rows */ if (png_ptr->prev_row != NULL) { png_bytep tptr; @@ -2770,7 +2772,7 @@ png_write_filtered_row(png_structp png_ptr, png_bytep filtered_row) png_ptr->row_buf = tptr; } - /* finish row - updates counters and flushes zlib if last row */ + /* Finish row - updates counters and flushes zlib if last row */ png_write_finish_row(png_ptr); #if defined(PNG_WRITE_FLUSH_SUPPORTED) |