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Guy Schalnat 1995-09-26 05:22:39 -05:00 committed by Glenn Randers-Pehrson
parent 0d5805822f
commit 51f0eb4584
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488
ansi2knr.c
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@ -1,488 +0,0 @@
/* Copyright (C) 1989, 1991, 1993 Aladdin Enterprises. All rights reserved. */
/* ansi2knr.c */
/* Convert ANSI function declarations to K&R syntax */
/*
ansi2knr is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY. No author or distributor accepts responsibility
to anyone for the consequences of using it or for whether it serves any
particular purpose or works at all, unless he says so in writing. Refer
to the GNU General Public License for full details.
Everyone is granted permission to copy, modify and redistribute
ansi2knr, but only under the conditions described in the GNU
General Public License. A copy of this license is supposed to have been
given to you along with ansi2knr so you can know your rights and
responsibilities. It should be in a file named COPYING. Among other
things, the copyright notice and this notice must be preserved on all
copies.
*/
/*
---------- Here is the GNU GPL file COPYING, referred to above ----------
----- These terms do NOT apply to the JPEG software itself; see README ------
GHOSTSCRIPT GENERAL PUBLIC LICENSE
(Clarified 11 Feb 1988)
Copyright (C) 1988 Richard M. Stallman
Everyone is permitted to copy and distribute verbatim copies of this
license, but changing it is not allowed. You can also use this wording
to make the terms for other programs.
The license agreements of most software companies keep you at the
mercy of those companies. By contrast, our general public license is
intended to give everyone the right to share Ghostscript. To make sure
that you get the rights we want you to have, we need to make
restrictions that forbid anyone to deny you these rights or to ask you
to surrender the rights. Hence this license agreement.
Specifically, we want to make sure that you have the right to give
away copies of Ghostscript, that you receive source code or else can get
it if you want it, that you can change Ghostscript or use pieces of it
in new free programs, and that you know you can do these things.
To make sure that everyone has such rights, we have to forbid you to
deprive anyone else of these rights. For example, if you distribute
copies of Ghostscript, you must give the recipients all the rights that
you have. You must make sure that they, too, receive or can get the
source code. And you must tell them their rights.
Also, for our own protection, we must make certain that everyone finds
out that there is no warranty for Ghostscript. If Ghostscript is
modified by someone else and passed on, we want its recipients to know
that what they have is not what we distributed, so that any problems
introduced by others will not reflect on our reputation.
Therefore we (Richard M. Stallman and the Free Software Foundation,
Inc.) make the following terms which say what you must do to be allowed
to distribute or change Ghostscript.
COPYING POLICIES
1. You may copy and distribute verbatim copies of Ghostscript source
code as you receive it, in any medium, provided that you conspicuously
and appropriately publish on each copy a valid copyright and license
notice "Copyright (C) 1989 Aladdin Enterprises. All rights reserved.
Distributed by Free Software Foundation, Inc." (or with whatever year is
appropriate); keep intact the notices on all files that refer to this
License Agreement and to the absence of any warranty; and give any other
recipients of the Ghostscript program a copy of this License Agreement
along with the program. You may charge a distribution fee for the
physical act of transferring a copy.
2. You may modify your copy or copies of Ghostscript or any portion of
it, and copy and distribute such modifications under the terms of
Paragraph 1 above, provided that you also do the following:
a) cause the modified files to carry prominent notices stating
that you changed the files and the date of any change; and
b) cause the whole of any work that you distribute or publish,
that in whole or in part contains or is a derivative of Ghostscript
or any part thereof, to be licensed at no charge to all third
parties on terms identical to those contained in this License
Agreement (except that you may choose to grant more extensive
warranty protection to some or all third parties, at your option).
c) You may charge a distribution fee for the physical act of
transferring a copy, and you may at your option offer warranty
protection in exchange for a fee.
Mere aggregation of another unrelated program with this program (or its
derivative) on a volume of a storage or distribution medium does not bring
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3. You may copy and distribute Ghostscript (or a portion or derivative
of it, under Paragraph 2) in object code or executable form under the
terms of Paragraphs 1 and 2 above provided that you also do one of the
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Paragraphs 1 and 2 above; or,
b) accompany it with a written offer, valid for at least three
years, to give any third party free (except for a nominal
shipping charge) a complete machine-readable copy of the
corresponding source code, to be distributed under the terms of
Paragraphs 1 and 2 above; or,
c) accompany it with the information you received as to where the
corresponding source code may be obtained. (This alternative is
allowed only for noncommercial distribution and only if you
received the program in object code or executable form alone.)
For an executable file, complete source code means all the source code for
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source code for modules which are standard libraries that accompany the
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4. You may not copy, sublicense, distribute or transfer Ghostscript
except as expressly provided under this License Agreement. Any attempt
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Your comments and suggestions about our licensing policies and our
software are welcome! Please contact the Free Software Foundation,
Inc., 675 Mass Ave, Cambridge, MA 02139, or call (617) 876-3296.
NO WARRANTY
BECAUSE GHOSTSCRIPT IS LICENSED FREE OF CHARGE, WE PROVIDE ABSOLUTELY
NO WARRANTY, TO THE EXTENT PERMITTED BY APPLICABLE STATE LAW. EXCEPT
WHEN OTHERWISE STATED IN WRITING, FREE SOFTWARE FOUNDATION, INC, RICHARD
M. STALLMAN, ALADDIN ENTERPRISES, L. PETER DEUTSCH, AND/OR OTHER PARTIES
PROVIDE GHOSTSCRIPT "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER
EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE
ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF GHOSTSCRIPT IS WITH
YOU. SHOULD GHOSTSCRIPT PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL
NECESSARY SERVICING, REPAIR OR CORRECTION.
IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW WILL RICHARD M.
STALLMAN, THE FREE SOFTWARE FOUNDATION, INC., L. PETER DEUTSCH, ALADDIN
ENTERPRISES, AND/OR ANY OTHER PARTY WHO MAY MODIFY AND REDISTRIBUTE
GHOSTSCRIPT AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING
ANY LOST PROFITS, LOST MONIES, OR OTHER SPECIAL, INCIDENTAL OR
CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE
(INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED
INACCURATE OR LOSSES SUSTAINED BY THIRD PARTIES OR A FAILURE OF THE
PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS) GHOSTSCRIPT, EVEN IF YOU
HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES, OR FOR ANY CLAIM
BY ANY OTHER PARTY.
-------------------- End of file COPYING ------------------------------
*/
#include <stdio.h>
#include <ctype.h>
#ifdef BSD
#include <strings.h>
#else
#ifdef VMS
extern int strlen(), strncmp();
#else
#include <string.h>
#endif
#endif
/* malloc and free should be declared in stdlib.h, */
/* but if you've got a K&R compiler, they probably aren't. */
#ifdef MSDOS
#include <malloc.h>
#else
#ifdef VMS
extern char *malloc();
extern void free();
#else
extern char *malloc();
extern int free();
#endif
#endif
/* Usage:
ansi2knr input_file [output_file]
* If no output_file is supplied, output goes to stdout.
* There are no error messages.
*
* ansi2knr recognizes functions by seeing a non-keyword identifier
* at the left margin, followed by a left parenthesis,
* with a right parenthesis as the last character on the line.
* It will recognize a multi-line header provided that the last character
* of the last line of the header is a right parenthesis,
* and no intervening line ends with a left brace or a semicolon.
* These algorithms ignore whitespace and comments, except that
* the function name must be the first thing on the line.
* The following constructs will confuse it:
* - Any other construct that starts at the left margin and
* follows the above syntax (such as a macro or function call).
* - Macros that tinker with the syntax of the function header.
*/
/* Scanning macros */
#define isidchar(ch) (isalnum(ch) || (ch) == '_')
#define isidfirstchar(ch) (isalpha(ch) || (ch) == '_')
/* Forward references */
char *skipspace();
int writeblanks();
int test1();
int convert1();
/* The main program */
main(argc, argv)
int argc;
char *argv[];
{ FILE *in, *out;
#define bufsize 5000 /* arbitrary size */
char *buf;
char *line;
switch ( argc )
{
default:
printf("Usage: ansi2knr input_file [output_file]\n");
exit(0);
case 2:
out = stdout; break;
case 3:
out = fopen(argv[2], "w");
if ( out == NULL )
{ fprintf(stderr, "Cannot open %s\n", argv[2]);
exit(1);
}
}
in = fopen(argv[1], "r");
if ( in == NULL )
{ fprintf(stderr, "Cannot open %s\n", argv[1]);
exit(1);
}
fprintf(out, "#line 1 \"%s\"\n", argv[1]);
buf = malloc(bufsize);
line = buf;
while ( fgets(line, (unsigned)(buf + bufsize - line), in) != NULL )
{ switch ( test1(buf) )
{
case 1: /* a function */
convert1(buf, out);
break;
case -1: /* maybe the start of a function */
line = buf + strlen(buf);
if ( line != buf + (bufsize - 1) ) /* overflow check */
continue;
/* falls through */
default: /* not a function */
fputs(buf, out);
break;
}
line = buf;
}
if ( line != buf ) fputs(buf, out);
free(buf);
fclose(out);
fclose(in);
return 0;
}
/* Skip over space and comments, in either direction. */
char *
skipspace(p, dir)
register char *p;
register int dir; /* 1 for forward, -1 for backward */
{ for ( ; ; )
{ while ( isspace(*p) ) p += dir;
if ( !(*p == '/' && p[dir] == '*') ) break;
p += dir; p += dir;
while ( !(*p == '*' && p[dir] == '/') )
{ if ( *p == 0 ) return p; /* multi-line comment?? */
p += dir;
}
p += dir; p += dir;
}
return p;
}
/*
* Write blanks over part of a string.
*/
int
writeblanks(start, end)
char *start;
char *end;
{ char *p;
for ( p = start; p < end; p++ ) *p = ' ';
return 0;
}
/*
* Test whether the string in buf is a function definition.
* The string may contain and/or end with a newline.
* Return as follows:
* 0 - definitely not a function definition;
* 1 - definitely a function definition;
* -1 - may be the beginning of a function definition,
* append another line and look again.
*/
int
test1(buf)
char *buf;
{ register char *p = buf;
char *bend;
char *endfn;
int contin;
if ( !isidfirstchar(*p) )
return 0; /* no name at left margin */
bend = skipspace(buf + strlen(buf) - 1, -1);
switch ( *bend )
{
case ')': contin = 1; break;
case '{':
case ';': return 0; /* not a function */
default: contin = -1;
}
while ( isidchar(*p) ) p++;
endfn = p;
p = skipspace(p, 1);
if ( *p++ != '(' )
return 0; /* not a function */
p = skipspace(p, 1);
if ( *p == ')' )
return 0; /* no parameters */
/* Check that the apparent function name isn't a keyword. */
/* We only need to check for keywords that could be followed */
/* by a left parenthesis (which, unfortunately, is most of them). */
{ static char *words[] =
{ "asm", "auto", "case", "char", "const", "double",
"extern", "float", "for", "if", "int", "long",
"register", "return", "short", "signed", "sizeof",
"static", "switch", "typedef", "unsigned",
"void", "volatile", "while", 0
};
char **key = words;
char *kp;
int len = endfn - buf;
while ( (kp = *key) != 0 )
{ if ( strlen(kp) == len && !strncmp(kp, buf, len) )
return 0; /* name is a keyword */
key++;
}
}
return contin;
}
int
convert1(buf, out)
char *buf;
FILE *out;
{ char *endfn;
register char *p;
char **breaks;
unsigned num_breaks = 2; /* for testing */
char **btop;
char **bp;
char **ap;
/* Pre-ANSI implementations don't agree on whether strchr */
/* is called strchr or index, so we open-code it here. */
for ( endfn = buf; *(endfn++) != '('; ) ;
top: p = endfn;
breaks = (char **)malloc(sizeof(char *) * num_breaks * 2);
if ( breaks == 0 )
{ /* Couldn't allocate break table, give up */
fprintf(stderr, "Unable to allocate break table!\n");
fputs(buf, out);
return -1;
}
btop = breaks + num_breaks * 2 - 2;
bp = breaks;
/* Parse the argument list */
do
{ int level = 0;
char *end = NULL;
if ( bp >= btop )
{ /* Filled up break table. */
/* Allocate a bigger one and start over. */
free((char *)breaks);
num_breaks <<= 1;
goto top;
}
*bp++ = p;
/* Find the end of the argument */
for ( ; end == NULL; p++ )
{ switch(*p)
{
case ',': if ( !level ) end = p; break;
case '(': level++; break;
case ')': if ( --level < 0 ) end = p; break;
case '/': p = skipspace(p, 1) - 1; break;
default: ;
}
}
p--; /* back up over terminator */
/* Find the name being declared. */
/* This is complicated because of procedure and */
/* array modifiers. */
for ( ; ; )
{ p = skipspace(p - 1, -1);
switch ( *p )
{
case ']': /* skip array dimension(s) */
case ')': /* skip procedure args OR name */
{ int level = 1;
while ( level )
switch ( *--p )
{
case ']': case ')': level++; break;
case '[': case '(': level--; break;
case '/': p = skipspace(p, -1) + 1; break;
default: ;
}
}
if ( *p == '(' && *skipspace(p + 1, 1) == '*' )
{ /* We found the name being declared */
while ( !isidfirstchar(*p) )
p = skipspace(p, 1) + 1;
goto found;
}
break;
default: goto found;
}
}
found: if ( *p == '.' && p[-1] == '.' && p[-2] == '.' )
{ p++;
if ( bp == breaks + 1 ) /* sole argument */
writeblanks(breaks[0], p);
else
writeblanks(bp[-1] - 1, p);
bp--;
}
else
{ while ( isidchar(*p) ) p--;
*bp++ = p+1;
}
p = end;
}
while ( *p++ == ',' );
*bp = p;
/* Make a special check for 'void' arglist */
if ( bp == breaks+2 )
{ p = skipspace(breaks[0], 1);
if ( !strncmp(p, "void", 4) )
{ p = skipspace(p+4, 1);
if ( p == breaks[2] - 1 )
{ bp = breaks; /* yup, pretend arglist is empty */
writeblanks(breaks[0], p + 1);
}
}
}
/* Put out the function name */
p = buf;
while ( p != endfn ) putc(*p, out), p++;
/* Put out the declaration */
for ( ap = breaks+1; ap < bp; ap += 2 )
{ p = *ap;
while ( isidchar(*p) ) putc(*p, out), p++;
if ( ap < bp - 1 ) fputs(", ", out);
}
fputs(") ", out);
/* Put out the argument declarations */
for ( ap = breaks+2; ap <= bp; ap += 2 ) (*ap)[-1] = ';';
fputs(breaks[0], out);
free((char *)breaks);
return 0;
}

63
example.c
View File

@ -6,6 +6,10 @@
designed to be a starting point of an implementation.
This is not officially part of libpng, and therefore
does not require a copyright notice.
This file does not currently compile, because it is missing
certain parts, like allocating memory to hold an image.
You will have to supply these parts to get it to compile.
*/
#include <png.h>
@ -81,15 +85,11 @@ void read_png(char *file_name)
/* read the file information */
png_read_info(png_ptr, info_ptr);
/* allocate the memory to hold the image using the fields
of png_info. */
/* set up the transformations you want. Note that these are
all optional. Only call them if you want them */
/* expand paletted colors into true rgb */
if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
info_ptr->bit_depth < 8)
if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
png_set_expand(png_ptr);
/* expand grayscale images to the full 8 bits */
@ -163,26 +163,32 @@ void read_png(char *file_name)
if (info_ptr->bit_depth == 16)
png_set_swap(png_ptr);
/* add a filler byte to store rgb files as rgbx */
/* add a filler byte to rgb files */
if (info_ptr->bit_depth == 8 &&
info_ptr->color_type == PNG_COLOR_TYPE_RGB)
png_set_rgbx(png_ptr);
png_set_filler(png_ptr, 0xff, PNG_FILLER_AFTER);
/* optional call to update palette with transformations */
png_start_read_image(png_ptr);
/* the easiest way to read the image */
void *row_pointers[height];
png_read_image(png_ptr, row_pointers);
/* the other way to read images - deal with interlacing */
/* turn on interlace handling */
/* turn on interlace handling if you are not using png_read_image() */
if (info_ptr->interlace_type)
number_passes = png_set_interlace_handling(png_ptr);
else
number_passes = 1;
/* optional call to update palette with transformations */
png_start_read_image(png_ptr);
/* optional call to update the info structure */
png_read_update_info(png_ptr, info_ptr);
/* allocate the memory to hold the image using the fields
of png_info. */
/* the easiest way to read the image */
png_bytef *row_pointers[height];
png_read_image(png_ptr, row_pointers);
/* the other way to read images - deal with interlacing */
for (pass = 0; pass < number_passes; pass++)
{
/* Read the image using the "sparkle" effect. */
@ -191,7 +197,7 @@ void read_png(char *file_name)
/* If you are only reading on row at a time, this works */
for (y = 0; y < height; y++)
{
char *row_pointers = row[y];
png_bytef *row_pointers = row[y];
png_read_rows(png_ptr, &row_pointers, NULL, 1);
}
@ -309,21 +315,22 @@ void write_png(char *file_name, ... other image information ...)
/* swap bytes of 16 bit files to most significant bit first */
png_set_swap(png_ptr);
/* get rid of filler bytes, pack rgb into 3 bytes */
png_set_rgbx(png_ptr);
/* get rid of filler bytes, pack rgb into 3 bytes. The
filler number is not used. */
png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
/* the easiest way to write the image */
void *row_pointers[height];
png_write_image(png_ptr, row_pointers);
/* the other way to write the image - deal with interlacing */
/* turn on interlace handling */
/* turn on interlace handling if you are not using png_write_image() */
if (interlacing)
number_passes = png_set_interlace_handling(png_ptr);
else
number_passes = 1;
/* the easiest way to write the image */
png_bytef *row_pointers[height];
png_write_image(png_ptr, row_pointers);
/* the other way to write the image - deal with interlacing */
for (pass = 0; pass < number_passes; pass++)
{
/* Write a few rows at a time. */
@ -332,7 +339,7 @@ void write_png(char *file_name, ... other image information ...)
/* If you are only writing one row at a time, this works */
for (y = 0; y < height; y++)
{
char *row_pointers = row[y];
png_bytef *row_pointers = row[y];
png_write_rows(png_ptr, &row_pointers, 1);
}
}

82
libpng.txt
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@ -1,9 +1,9 @@
libpng.txt - a description on how to use and modify libpng
libpng 1.0 beta 1 - version 0.71
libpng 1.0 beta 2 - version 0.8
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
June 26, 1995
August 20, 1995
This file describes how to use and modify the PNG reference library
(known as libpng) for your own use. There are four sections to this
@ -325,17 +325,21 @@ PC's store them, for example), call this:
png_set_swap(png_ptr);
PNG files store rgb pixels packed into 3 bytes. If you would rather
pack them into 4 bytes, with the filler byte last, call this:
pack them into 4 bytes, call this:
if (info_ptr->bit_depth == 8 &&
info_ptr->color_type == PNG_COLOR_TYPE_RGB)
png_set_rgbx(png_ptr);
png_set_filler(png_ptr, filler_byte, PNG_FILLER_BEFORE);
If you need the filler byte first, call this:
where filler_byte is the number to fill with, and the location is
either PNG_FILLER_BEFORE or PNG_FILLER_AFTER, depending upon whether
you want the filler before the rgb or after.
if (info_ptr->bit_depth == 8 &&
info_ptr->color_type == PNG_COLOR_TYPE_RGB)
png_set_xrgb(png_ptr);
Finally, if you need the interlacing as discussed below, call
this here:
if (info_ptr->interlace_type)
number_passes = png_set_interlace_handling(png_ptr);
After setting the transformations, you can update your palette by
calling png_start_read_image(). This function is provided for those
@ -345,7 +349,22 @@ before it reads the first row.
png_start_read_image(png_ptr);
That's it for the transformations. Now you can read the image data.
If you want, libpng will update your png_info structure to reflect
any transformations you've requested with this call. This is most
useful to update the info structures rowbytes field, so you can
use it to allocate your image memory. This function calls
png_start_read_image(), so you don't have to call both of them.
png_read_update_info(png_ptr, info_ptr);
After you call png_read_update_info(), you can allocate any
memory you need to hold the image. As the actual allocation
varies among applications, no example will be given. If you
are allocating one large chunk, you may find it useful to
build an array of pointers to each row, as it will be needed
for some of the functions below.
After you've allocated memory, you can read the image data.
The simplest way to do this is in one function call. If you are
allocating enough memory to hold the whole image, you can just
call png_read_image() and libpng will read in all the image data
@ -399,7 +418,7 @@ call png_read_rows() the correct number of times to read in all
seven images. See the PNG specification for more details on the
interlacing scheme.
If you want libpng to expand the images, call this:
If you want libpng to expand the images, call this above:
if (info_ptr->interlace_type)
number_passes = png_set_interlace_handling(png_ptr);
@ -521,6 +540,25 @@ Customizing Libpng section below.
png_init_io(png_ptr, fp);
You now have the option of modifying how the compression library
will run. The following functions are mainly for testing, but
may be useful in certain special cases, like if you need to
write png files extremely fast and are willing to give up some
compression, or if you want to get the maximum possible compression
at the expense of slower writing. If you have no special needs
in this area, let the library do what it wants, as it has been
carefully tuned to deliver the best speed/compression ratio.
See the compression library for more details.
/* turn on or off filtering (1 or 0) */
png_set_filtering(png_struct *png_ptr, 1);
png_set_compression_level(png_ptr, Z_DEFAULT_COMPRESSION);
png_set_compression_mem_level(png_ptr, 8);
png_set_compression_strategy(png_ptr, Z_DEFAULT_STRATEGY);
png_set_compression_window_bits(png_ptr, 15);
png_set_compression_method(png_ptr, 8);
You now need to fill in the png_info structure with all the data
you wish to write before the actual image. Note that the only thing
you are allowed to write after the image is the text chunks and the
@ -600,14 +638,13 @@ make sure to only enable a transformation if it will be valid for
the data. For example, don't swap red and blue on grayscale data.
PNG files store rgb pixels packed into 3 bytes. If you would rather
supply the pixels as 4 bytes per pixel, with the filler byte last,
call this:
supply the pixels as 4 bytes per pixel, call this:
png_set_rgbx(png_ptr);
png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
If your filler byte goes first, call this:
png_set_xrgb(png_ptr);
where the 0 is not used for writing, and the location is either
PNG_FILLER_BEFORE or PNG_FILLER_AFTER, depending upon whether you
want the filler before the rgb or after.
PNG files pack pixels of bit depths 1, 2, and 4 into bytes as small as
they can, resulting in, for example, 8 pixels per byte for 1 bit files.
@ -819,3 +856,16 @@ needed outside libpng are protected by the PNG_INTERNAL definition,
which is only defined for those routines inside libpng itself. The
files in libpng proper only include png.h.
Removing unwanted object code:
There are a bunch of #define's in png.h that control what parts of
libpng are compiled. All the defines end in _SUPPORT. If you are
not using an ability, you can change the #define to #undef and
save yourself code and data space. All the reading and writing
specific code are in seperate files, so the linker should only grab
the files it needs. However, if you want to make sure, or if you
are building a stand alone library, all the reading files start with
pngr and all the writing files start with pngw. The files that
don't match either (like png.c, pngtrans.c, etc.) are used for
both reading and writing, and always need to be included.

43
makefile
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@ -2,18 +2,19 @@
# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
# For conditions of distribution and use, see copyright notice in png.h
CC=gcc
CFLAGS=-I../zlib -O3
LDFLAGS=-L. -L../zlib/ -lpng -lgz -lm
CC=cc
CFLAGS=-I../zlib -O
LDFLAGS=-L. -L../zlib/ -lpng -lz -lm
RANLIB=ranlib
#RANLIB=echo
#RANLIB=ranlib
RANLIB=echo
# where make install puts libpng.a and png.h
prefix=/usr/local
OBJS = png.o pngrcb.o pngrutil.o pngtrans.o pngwutil.o \
pngread.o pngstub.o pngwrite.o pngrtran.o pngwtran.o
pngread.o pngio.o pngwrite.o pngrtran.o pngwtran.o \
pngmem.o pngerror.o
all: libpng.a pngtest
@ -22,13 +23,18 @@ libpng.a: $(OBJS)
$(RANLIB) $@
pngtest: pngtest.o libpng.a
cc -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS)
$(CC) -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS)
test: pngtest
./pngtest
install: libpng.a
-@mkdir $(prefix)/include
-@mkdir $(prefix)/lib
cp png.h $(prefix)/include
cp pngconf.h $(prefix)/include
chmod 644 $(prefix)/include/png.h
chmod 644 $(prefix)/include/pngconf.h
cp libpng.a $(prefix)/lib
chmod 644 $(prefix)/lib/libpng.a
@ -37,13 +43,16 @@ clean:
# DO NOT DELETE THIS LINE -- make depend depends on it.
pngrcb.o: png.h
pngread.o: png.h
pngrtran.o: png.h
pngrutil.o: png.h
pngstub.o: png.h
pngtest.o: png.h
pngtrans.o: png.h
pngwrite.o: png.h
pngwtran.o: png.h
pngwutil.o: png.h
png.o: png.h pngconf.h
pngerror.o: png.h pngconf.h
pngio.o: png.h pngconf.h
pngmem.o: png.h pngconf.h
pngrcb.o: png.h pngconf.h
pngread.o: png.h pngconf.h
pngrtran.o: png.h pngconf.h
pngrutil.o: png.h pngconf.h
pngtest.o: png.h pngconf.h
pngtrans.o: png.h pngconf.h
pngwrite.o: png.h pngconf.h
pngwtran.o: png.h pngconf.h
pngwutil.o: png.h pngconf.h

61
makefile.knr
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@ -1,61 +0,0 @@
# makefile for libpng
# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
# For conditions of distribution and use, see copyright notice in png.h
CC=cc
CFLAGS=-I../zlib -O
LDFLAGS=-L. -L../zlib/ -lpng -lgz -lm
# flags for ansi2knr
ANSI2KNRFLAGS=
RANLIB=ranlib
#RANLIB=echo
# where make install puts libpng.a and png.h
prefix=/usr/local
OBJS = png.o pngrcb.o pngrutil.o pngtrans.o pngwutil.o \
pngread.o pngstub.o pngwrite.o pngrtran.o pngwtran.o
all: ansi2knr libpng.a pngtest
# general rule to allow ansi2knr to work
.c.o:
./ansi2knr $*.c T$*.c
$(CC) $(CFLAGS) -c T$*.c
rm -f T$*.c $*.o
mv T$*.o $*.o
ansi2knr: ansi2knr.c
$(CC) $(CFLAGS) $(ANSI2KNRFLAGS) -o ansi2knr ansi2knr.c
libpng.a: ansi2knr $(OBJS)
ar rc $@ $(OBJS)
$(RANLIB) $@
pngtest: pngtest.o libpng.a ansi2knr
cc -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS)
install: libpng.a
-@mkdir $(prefix)/include
-@mkdir $(prefix)/lib
cp png.h $(prefix)/include
chmod 644 $(prefix)/include/png.h
cp libpng.a $(prefix)/lib
chmod 644 $(prefix)/lib/libpng.a
clean:
rm -f *.o libpng.a pngtest pngout.png ansi2knr
# DO NOT DELETE THIS LINE -- make depend depends on it.
pngrcb.o: png.h
pngread.o: png.h
pngrtran.o: png.h
pngrutil.o: png.h
pngstub.o: png.h
pngtest.o: png.h
pngtrans.o: png.h
pngwrite.o: png.h
pngwtran.o: png.h
pngwutil.o: png.h

50
makefile.mip
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@ -1,50 +0,0 @@
# makefile for libpng
# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
# For conditions of distribution and use, see copyright notice in png.h
CC=cc
CFLAGS=-I../zlib -O -systype sysv -DSYSV -w -Dmips
#CFLAGS=-O
LDFLAGS=-L. -L../zlib/ -lpng -lgz -lm
#RANLIB=ranlib
RANLIB=echo
# where make install puts libpng.a and png.h
prefix=/usr/local
OBJS = png.o pngrcb.o pngrutil.o pngtrans.o pngwutil.o \
pngread.o pngstub.o pngwrite.o pngrtran.o pngwtran.o
all: libpng.a pngtest
libpng.a: $(OBJS)
ar rc $@ $(OBJS)
$(RANLIB) $@
pngtest: pngtest.o libpng.a
cc -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS)
install: libpng.a
-@mkdir $(prefix)/include
-@mkdir $(prefix)/lib
cp png.h $(prefix)/include
chmod 644 $(prefix)/include/png.h
cp libpng.a $(prefix)/lib
chmod 644 $(prefix)/lib/libpng.a
clean:
rm -f *.o libpng.a pngtest pngout.png
# DO NOT DELETE THIS LINE -- make depend depends on it.
pngrcb.o: png.h
pngread.o: png.h
pngrtran.o: png.h
pngrutil.o: png.h
pngstub.o: png.h
pngtest.o: png.h
pngtrans.o: png.h
pngwrite.o: png.h
pngwtran.o: png.h
pngwutil.o: png.h

49
makefile.std
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@ -1,49 +0,0 @@
# makefile for libpng
# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
# For conditions of distribution and use, see copyright notice in png.h
CC=cc
CFLAGS=-I../zlib -O
LDFLAGS=-L. -L../zlib/ -lpng -lgz -lm
#RANLIB=ranlib
RANLIB=echo
# where make install puts libpng.a and png.h
prefix=/usr/local
OBJS = png.o pngrcb.o pngrutil.o pngtrans.o pngwutil.o \
pngread.o pngstub.o pngwrite.o pngrtran.o pngwtran.o
all: libpng.a pngtest
libpng.a: $(OBJS)
ar rc $@ $(OBJS)
$(RANLIB) $@
pngtest: pngtest.o libpng.a
cc -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS)
install: libpng.a
-@mkdir $(prefix)/include
-@mkdir $(prefix)/lib
cp png.h $(prefix)/include
chmod 644 $(prefix)/include/png.h
cp libpng.a $(prefix)/lib
chmod 644 $(prefix)/lib/libpng.a
clean:
rm -f *.o libpng.a pngtest pngout.png
# DO NOT DELETE THIS LINE -- make depend depends on it.
pngrcb.o: png.h
pngread.o: png.h
pngrtran.o: png.h
pngrutil.o: png.h
pngstub.o: png.h
pngtest.o: png.h
pngtrans.o: png.h
pngwrite.o: png.h
pngwtran.o: png.h
pngwutil.o: png.h

53
png.c
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@ -1,16 +1,20 @@
/* png.c - location for general purpose png functions
libpng 1.0 beta 1 - version 0.71
libpng 1.0 beta 2 - version 0.81
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
June 26, 1995
August 24, 1995
*/
#define PNG_INTERNAL
#define PNG_NO_EXTERN
#include "png.h"
/* version information for c files. This better match the version
string defined in png.h */
char png_libpng_ver[] = "0.81";
/* place to hold the signiture string for a png file. */
png_byte png_sig[8] = {137, 80, 78, 71, 13, 10, 26, 10};
@ -21,17 +25,39 @@ png_byte png_IHDR[4] = { 73, 72, 68, 82};
png_byte png_IDAT[4] = { 73, 68, 65, 84};
png_byte png_IEND[4] = { 73, 69, 78, 68};
png_byte png_PLTE[4] = { 80, 76, 84, 69};
#if defined(PNG_READ_gAMA_SUPPORTED) || defined(PNG_WRITE_gAMA_SUPPORTED)
png_byte png_gAMA[4] = {103, 65, 77, 65};
#endif
#if defined(PNG_READ_sBIT_SUPPORTED) || defined(PNG_WRITE_sBIT_SUPPORTED)
png_byte png_sBIT[4] = {115, 66, 73, 84};
#endif
#if defined(PNG_READ_cHRM_SUPPORTED) || defined(PNG_WRITE_cHRM_SUPPORTED)
png_byte png_cHRM[4] = { 99, 72, 82, 77};
#endif
#if defined(PNG_READ_tRNS_SUPPORTED) || defined(PNG_WRITE_tRNS_SUPPORTED)
png_byte png_tRNS[4] = {116, 82, 78, 83};
#endif
#if defined(PNG_READ_bKGD_SUPPORTED) || defined(PNG_WRITE_bKGD_SUPPORTED)
png_byte png_bKGD[4] = { 98, 75, 71, 68};
#endif
#if defined(PNG_READ_hIST_SUPPORTED) || defined(PNG_WRITE_hIST_SUPPORTED)
png_byte png_hIST[4] = {104, 73, 83, 84};
#endif
#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_WRITE_tEXt_SUPPORTED)
png_byte png_tEXt[4] = {116, 69, 88, 116};
#endif
#if defined(PNG_READ_zTXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
png_byte png_zTXt[4] = {122, 84, 88, 116};
#endif
#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
png_byte png_pHYs[4] = {112, 72, 89, 115};
#endif
#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
png_byte png_oFFs[4] = {111, 70, 70, 115};
#endif
#if defined(PNG_READ_tIME_SUPPORTED) || defined(PNG_WRITE_tIME_SUPPORTED)
png_byte png_tIME[4] = {116, 73, 77, 69};
#endif
/* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
@ -78,18 +104,18 @@ png_check_sig(png_byte *sig, int num)
}
/* Function to allocate memory for zlib. */
voidp
png_zalloc(voidp png_ptr, uInt items, uInt size)
voidpf
png_zalloc(voidpf png_ptr, uInt items, uInt size)
{
return ((voidp)png_large_malloc((png_struct *)png_ptr,
return ((voidpf)png_large_malloc((png_struct FAR *)png_ptr,
(png_uint_32)items * (png_uint_32)size));
}
/* function to free memory for zlib */
void
png_zfree(voidp png_ptr, voidp ptr)
png_zfree(voidpf png_ptr, voidpf ptr)
{
png_large_free((png_struct *)png_ptr, (void *)ptr);
png_large_free((png_struct FAR *)png_ptr, (voidpf)ptr);
}
/* reset the crc variable to 32 bits of 1's. Care must be taken
@ -135,10 +161,10 @@ make_crc_table(void)
initialized to all 1's, and the transmitted value is the 1's complement
of the final running crc. */
static png_uint_32
update_crc(png_uint_32 crc, png_byte *buf, png_uint_32 len)
update_crc(png_uint_32 crc, png_bytef *buf, png_uint_32 len)
{
png_uint_32 c;
png_byte *p;
png_bytef *p;
png_uint_32 n;
c = crc;
@ -163,10 +189,15 @@ update_crc(png_uint_32 crc, png_byte *buf, png_uint_32 len)
would need to use huge pointers to access all that data. If you
need this, put huge here and above. */
void
png_calculate_crc(png_struct *png_ptr, png_byte *ptr,
png_calculate_crc(png_struct *png_ptr, png_bytef *ptr,
png_uint_32 length)
{
png_ptr->crc = update_crc(png_ptr->crc, ptr, length);
}
void
png_info_init(png_info *info)
{
/* set everything to 0 */
memset(info, 0, sizeof (png_info));
}

620
png.h
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File diff suppressed because it is too large Load Diff

16
pngchang.txt
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@ -40,5 +40,21 @@ version 0.7
version 0.71
changed pngtest.png for zlib 0.93
fixed error in libpng.txt and example.c
version 0.8
cleaned up some bugs
added png_set_filler()
split up pngstub.c into pngmem.c, pngio.c, and pngerror.c
added #define's to remove unwanted code
moved png_info_init() to png.c
added old_size into png_realloc()
added functions to manually set filtering and compression info
changed compression parameters based on image type
optimized filter selection code
added version info
changed external functions passing floats to doubles (k&r problems?)
put all the configurable stuff in pngconf.h
enabled png_set_shift to work with paletted images on read
added png_read_update_info() - updates info structure with transformations

256
pngconf.h Normal file
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@ -0,0 +1,256 @@
/* pngconf.c - machine configurable file for libpng
libpng 1.0 beta 2 - version 0.81
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
August 24, 1995
*/
/* Any machine specific code is near the front of this file, so if you
are configuring libpng for a machine, you may want to read the section
starting here down to where it starts to typedef png_color, png_text,
and png_info */
#ifndef PNGCONF_H
#define PNGCONF_H
/* this is the size of the compression buffer, and thus the size of
an IDAT chunk. Make this whatever size you feel is best for your
machine. One of these will be allocated per png_struct. When this
is full, it writes the data to the disk, and does some other
calculations. Making this an extreamly small size will slow
the library down, but you may want to experiment to determine
where it becomes significant, if you are concerned with memory
usage. Note that zlib allocates at least 32Kb also. For readers,
this describes the size of the buffer available to read the data in.
Unless this gets smaller then the size of a row (compressed),
it should not make much difference how big this is. */
#define PNG_ZBUF_SIZE 8192
/* While libpng currently uses zlib for it's compression, it has been designed
to stand on it's own. Towards this end, there are two defines that are
used to help portability between machines. To make it simpler to
setup libpng on a machine, this currently uses zlib's definitions, so
any changes should be made in zlib. Libpng will check zlib's settings
and adjust it's own accordingly. */
/* if you are running on a machine where you cannot allocate more then
64K of memory, uncomment this. While libpng will not normally need
that much memory in a chunk (unless you load up a very large file),
zlib needs to know how big of a chunk it can use, and libpng thus
makes sure to check any memory allocation to verify it will fit
into memory.
#define PNG_MAX_ALLOC_64K
*/
#ifdef MAXSEG_64K
#define PNG_MAX_ALLOC_64K
#endif
/* this macro protects us against machines that don't have function
prototypes. If your compiler does not handle function prototypes,
define this macro. I've always been able to use _NO_PROTO as the
indicator, but you may need to drag the empty declaration out in
front of here, or change the ifdef to suit your own needs. */
#ifndef PNGARG
#ifdef OF
#define PNGARG(arglist) OF(arglist)
#else
#ifdef _NO_PROTO
#define PNGARG(arglist)
#else
#define PNGARG(arglist) arglist
#endif /* _NO_PROTO */
#endif /* OF */
#endif /* PNGARG */
/* enough people need this for various reasons to include it here */
#ifndef MACOS
#include <sys/types.h>
#endif
/* need the time information for reading tIME chunks */
#include <time.h>
/* for FILE. If you are not using standard io, you don't need this */
#include <stdio.h>
/* include setjmp.h for error handling */
#include <setjmp.h>
#ifdef BSD
#include <strings.h>
#else
#include <string.h>
#endif
/* other defines for things like memory and the like can go here. These
are the only files included in libpng, so if you need to change them,
change them here. They are only included if PNG_INTERNAL is defined. */
#ifdef PNG_INTERNAL
#include <stdlib.h>
#include <ctype.h>
#include <math.h>
/* other defines specific to compilers can go here. Try to keep
them inside an appropriate ifdef/endif pair for portability */
/* for some reason, Borland C++ defines memcmp, etc. in mem.h, not
stdlib.h like it should (I think). Or perhaps this is a C++
feature */
#ifdef __TURBOC__
#include <mem.h>
#include "alloc.h"
#endif
#ifdef _MSC_VER
#include <malloc.h>
#endif
/* this controls how fine the dithering gets. As this allocates
a largish chunk of memory (32K), those who are not as concerned
with dithering quality can decrease some or all of these */
#define PNG_DITHER_RED_BITS 5
#define PNG_DITHER_GREEN_BITS 5
#define PNG_DITHER_BLUE_BITS 5
/* this controls how fine the gamma correction becomes when you
are only interested in 8 bits anyway. Increasing this value
results in more memory being used, and more pow() functions
being called to fill in the gamma tables. Don't get this
value less then 8, and even that may not work (I haven't tested
it). */
#define PNG_MAX_GAMMA_8 11
#endif /* PNG_INTERNAL */
/* The following defines give you the ability to remove code
from the library that you will not be using. I wish I
could figure out how to automate this, but I can't do
that without making it seriously hard on the users. So
if you are not using an ability, change the #define to
and #undef, and that part of the library will not be
compiled. If your linker can't find a function, you
may want to make sure the ability is defined here.
Some of these depend upon some others being defined.
I haven't figured out all the interactions here, so
you may have to experiment awhile to get everything
to compile.
*/
/* Any transformations you will not be using can be undef'ed here */
#define PNG_READ_INTERLACING_SUPPORTED
#define PNG_READ_EXPAND_SUPPORTED
#define PNG_READ_SHIFT_SUPPORTED
#define PNG_READ_PACK_SUPPORTED
#define PNG_READ_BGR_SUPPORTED
#define PNG_READ_SWAP_SUPPORTED
#define PNG_READ_INVERT_SUPPORTED
#define PNG_READ_DITHER_SUPPORTED
#define PNG_READ_BACKGROUND_SUPPORTED
#define PNG_READ_16_TO_8_SUPPORTED
#define PNG_READ_FILLER_SUPPORTED
#define PNG_READ_GAMMA_SUPPORTED
#define PNG_READ_GRAY_TO_RGB_SUPPORTED
#define PNG_WRITE_INTERLACING_SUPPORTED
#define PNG_WRITE_SHIFT_SUPPORTED
#define PNG_WRITE_PACK_SUPPORTED
#define PNG_WRITE_BGR_SUPPORTED
#define PNG_WRITE_SWAP_SUPPORTED
#define PNG_WRITE_INVERT_SUPPORTED
#define PNG_WRITE_FILLER_SUPPORTED
/* any chunks you are not interested in, you can undef here. The
ones that allocate memory may be expecially important (hIST,
tEXt, zTXt, tRNS) Others will just save time and make png_info
smaller. OPT_PLTE only disables the optional palette in RGB
and RGB Alpha images. */
#define PNG_READ_gAMA_SUPPORTED
#define PNG_READ_sBIT_SUPPORTED
#define PNG_READ_cHRM_SUPPORTED
#define PNG_READ_tRNS_SUPPORTED
#define PNG_READ_bKGD_SUPPORTED
#define PNG_READ_hIST_SUPPORTED
#define PNG_READ_pHYs_SUPPORTED
#define PNG_READ_oFFs_SUPPORTED
#define PNG_READ_tIME_SUPPORTED
#define PNG_READ_tEXt_SUPPORTED
#define PNG_READ_zTXt_SUPPORTED
#define PNG_READ_OPT_PLTE_SUPPORTED
#define PNG_WRITE_gAMA_SUPPORTED
#define PNG_WRITE_sBIT_SUPPORTED
#define PNG_WRITE_cHRM_SUPPORTED
#define PNG_WRITE_tRNS_SUPPORTED
#define PNG_WRITE_bKGD_SUPPORTED
#define PNG_WRITE_hIST_SUPPORTED
#define PNG_WRITE_pHYs_SUPPORTED
#define PNG_WRITE_oFFs_SUPPORTED
#define PNG_WRITE_tIME_SUPPORTED
#define PNG_WRITE_tEXt_SUPPORTED
#define PNG_WRITE_zTXt_SUPPORTED
/* some typedefs to get us started. These should be safe on most of the
common platforms. The typedefs should be at least as large
as the numbers suggest (a png_uint_32 must be at least 32 bits long),
but they don't have to be exactly that size. */
typedef unsigned long png_uint_32;
typedef long png_int_32;
typedef unsigned short png_uint_16;
typedef short png_int_16;
typedef unsigned char png_byte;
/* this is usually size_t. it is typedef'ed just in case you need it to
change (I'm not sure if you will or not, so I thought I'd be safe) */
typedef size_t png_size_t;
/* The following is needed for medium model support. It cannot be in the
PNG_INTERNAL section. Needs modification for other compilers besides
MSC. Model independent support declares all arrays that might be very
large using the far keyword. The Zlib version used must also support
model independent data. As of version Zlib .95, the necessary changes
have been made in Zlib. The USE_FAR_KEYWORD define triggers other
changes that are needed. Most of the far keyword changes are hidden
inside typedefs with suffix "f". Tim Wegner */
#if defined(FAR) && defined(M_I86MM) /* MSC Medium model */
# define USE_FAR_KEYWORD
#else
# define FAR
#endif
typedef unsigned char FAR png_bytef;
/* End medium model changes to be in zconf.h */
/* User may want to use these so not in PNG_INTERNAL. Any library functions
that are passed far data must be model independent. */
#if defined(USE_FAR_KEYWORD) /* memory model independent fns */
# define png_strcpy _fstrcpy
# define png_strcat _fstrcat
# define png_strlen _fstrlen
# define png_strcmp _fstrcmp
# define png_memcpy _fmemcpy
# define png_memset _fmemset
#else /* use the usual functions */
# define png_strcpy strcpy
# define png_strcat strcat
# define png_strlen strlen
# define png_strcmp strcmp
# define png_memcpy memcpy
# define png_memset memset
#endif
/* End of memory model independent support */
#endif /* PNGCONF_H */

46
pngerror.c Normal file
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@ -0,0 +1,46 @@
/* pngstub.c - stub functions for i/o and memory allocation
libpng 1.0 beta 2 - version 0.81
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
August 24, 1995
This file provides a location for all error handling. Users which
need special error handling are expected to modify the code in this
file to meet their needs. See the instructions at each function. */
#define PNG_INTERNAL
#include "png.h"
/* This function is called whenever there is an error. Replace with
however you wish to handle the error. Note that this function
MUST NOT return, or the program will crash */
void
png_error(png_structf *png_ptr, char *message)
{
fprintf(stderr, "libpng error: %s\n", message);
#ifdef USE_FAR_KEYWORD
{
jmp_buf jmpbuf;
png_memcpy(jmpbuf,png_ptr->jmpbuf,sizeof(jmp_buf));
longjmp(jmpbuf, 1);
}
#else
longjmp(png_ptr->jmpbuf, 1);
#endif
}
/* This function is called when there is a warning, but the library
thinks it can continue anyway. You don't have to do anything here
if you don't want to. In the default configuration, png_ptr is
not used, but it is passed in case it may be useful. */
void
png_warning(png_struct *png_ptr, char *message)
{
if (!png_ptr)
return;
fprintf(stderr, "libpng warning: %s\n", message);
}

180
pngio.c Normal file
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@ -0,0 +1,180 @@
</