12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 */
24
25 /* pngwutil.c - utilities to write a PNG file
26 *
27 * This file is available under and governed by the GNU General Public
28 * License version 2 only, as published by the Free Software Foundation.
29 * However, the following notice accompanied the original version of this
30 * file and, per its terms, should not be removed:
31 *
32 * Last changed in libpng 1.6.19 [November 12, 2015]
33 * Copyright (c) 1998-2015 Glenn Randers-Pehrson
34 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
35 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
36 *
37 * This code is released under the libpng license.
38 * For conditions of distribution and use, see the disclaimer
39 * and license in png.h
40 */
41
42 #include "pngpriv.h"
43
44 #ifdef PNG_WRITE_SUPPORTED
45
46 #ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
47 /* Place a 32-bit number into a buffer in PNG byte order. We work
48 * with unsigned numbers for convenience, although one supported
49 * ancillary chunk uses signed (two's complement) numbers.
50 */
51 void PNGAPI
52 png_save_uint_32(png_bytep buf, png_uint_32 i)
53 {
54 buf[0] = (png_byte)(i >> 24);
55 buf[1] = (png_byte)(i >> 16);
56 buf[2] = (png_byte)(i >> 8);
57 buf[3] = (png_byte)(i );
58 }
59
60 /* Place a 16-bit number into a buffer in PNG byte order.
61 * The parameter is declared unsigned int, not png_uint_16,
62 * just to avoid potential problems on pre-ANSI C compilers.
63 */
64 void PNGAPI
65 png_save_uint_16(png_bytep buf, unsigned int i)
66 {
67 buf[0] = (png_byte)(i >> 8);
68 buf[1] = (png_byte)(i );
69 }
70 #endif
71
72 /* Simple function to write the signature. If we have already written
73 * the magic bytes of the signature, or more likely, the PNG stream is
74 * being embedded into another stream and doesn't need its own signature,
75 * we should call png_set_sig_bytes() to tell libpng how many of the
76 * bytes have already been written.
77 */
78 void PNGAPI
79 png_write_sig(png_structrp png_ptr)
80 {
81 png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10};
82
83 #ifdef PNG_IO_STATE_SUPPORTED
84 /* Inform the I/O callback that the signature is being written */
85 png_ptr->io_state = PNG_IO_WRITING | PNG_IO_SIGNATURE;
86 #endif
87
88 /* Write the rest of the 8 byte signature */
676 avail = output_len;
677
678 png_write_chunk_data(png_ptr, output, avail);
679
680 output_len -= avail;
681
682 if (output_len == 0 || next == NULL)
683 break;
684
685 avail = png_ptr->zbuffer_size;
686 output = next->output;
687 next = next->next;
688 }
689
690 /* This is an internal error; 'next' must have been NULL! */
691 if (output_len > 0)
692 png_error(png_ptr, "error writing ancillary chunked compressed data");
693 }
694 #endif /* WRITE_COMPRESSED_TEXT */
695
696 #if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
697 defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
698 /* Check that the tEXt or zTXt keyword is valid per PNG 1.0 specification,
699 * and if invalid, correct the keyword rather than discarding the entire
700 * chunk. The PNG 1.0 specification requires keywords 1-79 characters in
701 * length, forbids leading or trailing whitespace, multiple internal spaces,
702 * and the non-break space (0x80) from ISO 8859-1. Returns keyword length.
703 *
704 * The 'new_key' buffer must be 80 characters in size (for the keyword plus a
705 * trailing '\0'). If this routine returns 0 then there was no keyword, or a
706 * valid one could not be generated, and the caller must png_error.
707 */
708 static png_uint_32
709 png_check_keyword(png_structrp png_ptr, png_const_charp key, png_bytep new_key)
710 {
711 png_const_charp orig_key = key;
712 png_uint_32 key_len = 0;
713 int bad_character = 0;
714 int space = 1;
715
716 png_debug(1, "in png_check_keyword");
717
718 if (key == NULL)
719 {
720 *new_key = 0;
721 return 0;
722 }
723
724 while (*key && key_len < 79)
725 {
726 png_byte ch = (png_byte)*key++;
727
728 if ((ch > 32 && ch <= 126) || (ch >= 161 /*&& ch <= 255*/))
729 *new_key++ = ch, ++key_len, space = 0;
730
731 else if (space == 0)
732 {
733 /* A space or an invalid character when one wasn't seen immediately
734 * before; output just a space.
735 */
736 *new_key++ = 32, ++key_len, space = 1;
737
738 /* If the character was not a space then it is invalid. */
739 if (ch != 32)
740 bad_character = ch;
741 }
742
743 else if (bad_character == 0)
744 bad_character = ch; /* just skip it, record the first error */
745 }
746
747 if (key_len > 0 && space != 0) /* trailing space */
748 {
749 --key_len, --new_key;
750 if (bad_character == 0)
751 bad_character = 32;
752 }
753
754 /* Terminate the keyword */
755 *new_key = 0;
756
757 if (key_len == 0)
758 return 0;
759
760 #ifdef PNG_WARNINGS_SUPPORTED
761 /* Try to only output one warning per keyword: */
762 if (*key != 0) /* keyword too long */
763 png_warning(png_ptr, "keyword truncated");
764
765 else if (bad_character != 0)
766 {
767 PNG_WARNING_PARAMETERS(p)
768
769 png_warning_parameter(p, 1, orig_key);
770 png_warning_parameter_signed(p, 2, PNG_NUMBER_FORMAT_02x, bad_character);
771
772 png_formatted_warning(png_ptr, p, "keyword \"@1\": bad character '0x@2'");
773 }
774 #endif /* WARNINGS */
775
776 return key_len;
777 }
778 #endif /* WRITE_TEXT || WRITE_pCAL || WRITE_iCCP || WRITE_sPLT */
779
780 /* Write the IHDR chunk, and update the png_struct with the necessary
781 * information. Note that the rest of this code depends upon this
782 * information being correct.
783 */
784 void /* PRIVATE */
785 png_write_IHDR(png_structrp png_ptr, png_uint_32 width, png_uint_32 height,
786 int bit_depth, int color_type, int compression_type, int filter_type,
787 int interlace_type)
788 {
789 png_byte buf[13]; /* Buffer to store the IHDR info */
790
791 png_debug(1, "in png_write_IHDR");
792
793 /* Check that we have valid input data from the application info */
794 switch (color_type)
795 {
796 case PNG_COLOR_TYPE_GRAY:
797 switch (bit_depth)
798 {
799 case 1:
|
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 */
24
25 /* pngwutil.c - utilities to write a PNG file
26 *
27 * This file is available under and governed by the GNU General Public
28 * License version 2 only, as published by the Free Software Foundation.
29 * However, the following notice accompanied the original version of this
30 * file and, per its terms, should not be removed:
31 *
32 * Last changed in libpng 1.6.22 [May 26, 2016]
33 * Copyright (c) 1998-2002,2004,2006-2016 Glenn Randers-Pehrson
34 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
35 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
36 *
37 * This code is released under the libpng license.
38 * For conditions of distribution and use, see the disclaimer
39 * and license in png.h
40 */
41
42 #include "pngpriv.h"
43
44 #ifdef PNG_WRITE_SUPPORTED
45
46 #ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
47 /* Place a 32-bit number into a buffer in PNG byte order. We work
48 * with unsigned numbers for convenience, although one supported
49 * ancillary chunk uses signed (two's complement) numbers.
50 */
51 void PNGAPI
52 png_save_uint_32(png_bytep buf, png_uint_32 i)
53 {
54 buf[0] = (png_byte)((i >> 24) & 0xffU);
55 buf[1] = (png_byte)((i >> 16) & 0xffU);
56 buf[2] = (png_byte)((i >> 8) & 0xffU);
57 buf[3] = (png_byte)( i & 0xffU);
58 }
59
60 /* Place a 16-bit number into a buffer in PNG byte order.
61 * The parameter is declared unsigned int, not png_uint_16,
62 * just to avoid potential problems on pre-ANSI C compilers.
63 */
64 void PNGAPI
65 png_save_uint_16(png_bytep buf, unsigned int i)
66 {
67 buf[0] = (png_byte)((i >> 8) & 0xffU);
68 buf[1] = (png_byte)( i & 0xffU);
69 }
70 #endif
71
72 /* Simple function to write the signature. If we have already written
73 * the magic bytes of the signature, or more likely, the PNG stream is
74 * being embedded into another stream and doesn't need its own signature,
75 * we should call png_set_sig_bytes() to tell libpng how many of the
76 * bytes have already been written.
77 */
78 void PNGAPI
79 png_write_sig(png_structrp png_ptr)
80 {
81 png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10};
82
83 #ifdef PNG_IO_STATE_SUPPORTED
84 /* Inform the I/O callback that the signature is being written */
85 png_ptr->io_state = PNG_IO_WRITING | PNG_IO_SIGNATURE;
86 #endif
87
88 /* Write the rest of the 8 byte signature */
676 avail = output_len;
677
678 png_write_chunk_data(png_ptr, output, avail);
679
680 output_len -= avail;
681
682 if (output_len == 0 || next == NULL)
683 break;
684
685 avail = png_ptr->zbuffer_size;
686 output = next->output;
687 next = next->next;
688 }
689
690 /* This is an internal error; 'next' must have been NULL! */
691 if (output_len > 0)
692 png_error(png_ptr, "error writing ancillary chunked compressed data");
693 }
694 #endif /* WRITE_COMPRESSED_TEXT */
695
696 /* Write the IHDR chunk, and update the png_struct with the necessary
697 * information. Note that the rest of this code depends upon this
698 * information being correct.
699 */
700 void /* PRIVATE */
701 png_write_IHDR(png_structrp png_ptr, png_uint_32 width, png_uint_32 height,
702 int bit_depth, int color_type, int compression_type, int filter_type,
703 int interlace_type)
704 {
705 png_byte buf[13]; /* Buffer to store the IHDR info */
706
707 png_debug(1, "in png_write_IHDR");
708
709 /* Check that we have valid input data from the application info */
710 switch (color_type)
711 {
712 case PNG_COLOR_TYPE_GRAY:
713 switch (bit_depth)
714 {
715 case 1:
|