Google Git
Sign in
skia / third_party / libpng / v1.7.0beta76 / . / contrib / examples / pngcp.c
blob: c9c051287d5b75b8829445c1ff9dd2af098d752f [file] [log] [blame]
/* pngcp.c
*
* Copyright (c) 2016 John Cunningham Bowler
*
* Last changed in libpng 1.7.0 [(PENDING RELEASE)]
*
* This code is released under the libpng license.
* For conditions of distribution and use, see the disclaimer
* and license in png.h
*
* This is a minimal example of copying a PNG without changes using the
* png_read_png and png_write_png interfaces.
*
* For a more extensive example that uses the transforms see
* contrib/libtests/pngimage.c in the libpng distribution.
*/
#define _POSIX_SOURCE 1
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <stdio.h>
#include <assert.h>
#include <unistd.h>
#include <sys/stat.h>
#if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
# include <config.h>
#endif
/* Define the following to use this test against your installed libpng, rather
* than the one being built here:
*/
#ifdef PNG_FREESTANDING_TESTS
# include <png.h>
#else
# include "../../png.h"
#endif
#include <zlib.h>
#ifndef PNG_SETJMP_SUPPORTED
# include <setjmp.h> /* because png.h did *not* include this */
#endif
#ifdef __GNUC__
/* Many versions of GCC erroneously report that local variables unmodified
* within the scope of a setjmp may be clobbered. This hacks round the
* problem (sometimes) without harming other compilers.
*/
# define gv volatile
#else
# define gv
#endif
#if PNG_LIBPNG_VER < 10700
/* READ_PNG and WRITE_PNG were not defined, so: */
# ifdef PNG_INFO_IMAGE_SUPPORTED
# ifdef PNG_SEQUENTIAL_READ_SUPPORTED
# define PNG_READ_PNG_SUPPORTED
# endif /* SEQUENTIAL_READ */
# ifdef PNG_WRITE_SUPPORTED
# define PNG_WRITE_PNG_SUPPORTED
# endif /* WRITE */
# endif /* INFO_IMAGE */
#endif /* pre 1.7.0 */
#if (defined(PNG_READ_PNG_SUPPORTED)) && (defined(PNG_WRITE_PNG_SUPPORTED))
/* This structure is used to control the test of a single file. */
typedef enum
{
VERBOSE, /* switches on all messages */
INFORMATION,
WARNINGS, /* switches on warnings */
LIBPNG_WARNING,
APP_WARNING,
ERRORS, /* just errors */
APP_FAIL, /* continuable error - no need to longjmp */
LIBPNG_ERROR, /* this and higher cause a longjmp */
LIBPNG_BUG, /* erroneous behavior in libpng */
APP_ERROR, /* such as out-of-memory in a callback */
QUIET, /* no normal messages */
USER_ERROR, /* such as file-not-found */
INTERNAL_ERROR
} error_level;
#define LEVEL_MASK 0xf /* where the level is in 'options' */
#define STRICT 0x010 /* Fail on warnings as well as errors */
#define LOG 0x020 /* Log pass/fail to stdout */
#define CONTINUE 0x040 /* Continue on APP_FAIL errors */
#define SIZES 0x080 /* Report input and output sizes */
#define OPTION 0x80000000 /* Used for handling options */
#define LIST 0x80000001 /* Used for handling options */
/* Result masks apply to the result bits in the 'results' field below; these
* bits are simple 1U<<error_level. A pass requires either nothing worse than
* warnings (--relaxes) or nothing worse than information (--strict)
*/
#define RESULT_STRICT(r) (((r) & ~((1U<<WARNINGS)-1)) == 0)
#define RESULT_RELAXED(r) (((r) & ~((1U<<ERRORS)-1)) == 0)
/* OPTION DEFINITIONS */
static const char range_lo[] = "min";
static const char range_hi[] = "max";
static const char all[] = "all";
#define RANGE(lo,hi) { range_lo, lo }, { range_hi, hi }
static const struct value_list
{
const char *name; /* the command line name of the value */
const int value; /* the actual value to use */
}
#if defined(PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED) ||\
defined(PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED)
vl_strategy[] =
{
/* This controls the order of search and also the default (which is huffman
* only compression):
*/
{ "fixed", Z_FIXED },
{ "huffman", Z_HUFFMAN_ONLY },
{ "RLE", Z_RLE },
{ "filtered", Z_FILTERED },
{ "default", Z_DEFAULT_STRATEGY },
{ all, 0 }
},
vl_level[] =
{
{ "default", Z_DEFAULT_COMPRESSION /* this is -1 */ },
{ "none", Z_NO_COMPRESSION },
{ "speed", Z_BEST_SPEED },
{ "best", Z_BEST_COMPRESSION },
RANGE(0, 9),
{ all, 0 }
},
vl_windowBits[] =
{
{ "default", 15 },
{ "small", 9 },
RANGE(8, 15),
{ all, 0 }
},
vl_memLevel[] =
{
{ "default", 8 },
{ "least", 1 },
RANGE(1, 9),
{ all, 0 }
},
#endif /* WRITE_CUSTOMIZE_*COMPRESSION */
#ifdef PNG_WRITE_FILTER_SUPPORTED
vl_filter[] =
{
{ all, PNG_ALL_FILTERS },
{ "off", PNG_NO_FILTERS },
{ "none", PNG_FILTER_NONE },
{ "sub", PNG_FILTER_SUB },
{ "up", PNG_FILTER_UP },
{ "avg", PNG_FILTER_AVG },
{ "paeth", PNG_FILTER_PAETH }
},
#endif /* WRITE_FILTER */
#define SELECT_HEURISTICALLY 1
#define SELECT_METHODICALLY 2
#if defined(PNG_SELECT_FILTER_HEURISTICALLY_SUPPORTED) ||\
defined(PNG_SELECT_FILTER_METHODICALLY_SUPPORTED)
vl_select[] =
{
{ all, SELECT_HEURISTICALLY|SELECT_METHODICALLY },
{ "off", 0 },
#ifdef PNG_SELECT_FILTER_HEURISTICALLY_SUPPORTED
{ "heuristically", SELECT_HEURISTICALLY },
#endif /* SELECT_FILTER_HEURISTICALLY */
#ifdef PNG_SELECT_FILTER_METHODICALLY_SUPPORTED
{ "methodically", SELECT_METHODICALLY },
#endif /* SELECT_FILTER_METHODICALLY */
{ "both", SELECT_HEURISTICALLY|SELECT_METHODICALLY }
},
#endif /* SELECT_FILTER_HEURISTICALLY || SELECT_FILTER_METHODICALLY */
vl_on_off[] = { { "on", 1 }, { "off", 2 } };
static const struct option
{
const char *name; /* name of the option */
png_uint_32 opt; /* an option, or OPTION or LIST */
png_byte value_count; /* length of the list of values: */
const struct value_list *values; /* values for OPTION or LIST */
} options[] =
{
/* struct display options, these are set when the command line is read */
# define S(n,v) { #n, v, 2, vl_on_off },
S(verbose, VERBOSE)
S(warnings, WARNINGS)
S(errors, ERRORS)
S(quiet, QUIET)
S(strict, STRICT)
S(log, LOG)
S(continue, CONTINUE)
S(sizes, SIZES)
# undef S
/* OPTION settings, these and LIST settings are read on demand */
# define VL(oname, name, type)\
{ oname, type, (sizeof vl_ ## name)/(sizeof vl_ ## name[0]), vl_ ## name },
# define VLO(oname, name) VL(oname, name, OPTION)
# ifdef PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED
# define VLCIDAT(name) VLO(#name, name)
# else
# define VLCIDAT(name)
# endif /* WRITE_CUSTOMIZE_COMPRESSION */
# ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
# define VLCzTXt(name) VLO("text-" #name, name)
# else
# define VLCzTXt(name)
# endif /* WRITE_CUSTOMIZE_ZTXT_COMPRESSION */
# define VLC(name) VLCIDAT(name) VLCzTXt(name)
VLC(strategy)
VLC(level)
VLC(windowBits)
VLC(memLevel)
# undef VLO
/* LIST settings */
# define VLL(name) VL(#name, name, LIST)
#if defined(PNG_SELECT_FILTER_HEURISTICALLY_SUPPORTED) ||\
defined(PNG_SELECT_FILTER_METHODICALLY_SUPPORTED)
VLL(select)
#endif /* SELECT_FILTER_HEURISTICALLY || SELECT_FILTER_METHODICALLY */
#ifdef PNG_WRITE_FILTER_SUPPORTED
VLL(filter)
#endif /* WRITE_FILTER */
# undef VLL
# undef VL
};
#define opt_count ((sizeof options)/(sizeof options[0]))
struct display
{
jmp_buf error_return; /* Where to go to on error */
unsigned int errset; /* error_return is set */
const char *operation; /* What is happening */
const char *filename; /* The name of the original file */
const char *output_file; /* The name of the output file */
/* Base file information */
png_uint_32 w;
png_uint_32 h;
int bpp;
png_alloc_size_t size;
/* Used on both read and write: */
FILE *fp;
/* Used on a read, both the original read and when validating a written
* image.
*/
png_alloc_size_t read_size;
png_structp read_pp;
png_infop ip;
/* Used to write a new image (the original info_ptr is used) */
png_alloc_size_t write_size;
png_alloc_size_t best_size;
png_structp write_pp;
/* Options handling */
png_uint_32 results; /* A mask of errors seen */
png_uint_32 options; /* See display_log below */
png_byte entry[opt_count]; /* The selected entry+1 of an option that
* appears on the command line, or 0 if
* it was not given. */
int value[opt_count]; /* Corresponding value */
/* Compression exhaustive testing */
/* Temporary variables used only while testing a single collectiono of
* settings:
*/
unsigned int csp; /* next stack entry to use */
unsigned int nsp; /* highest active entry+1 found so far */
/* Values used while iterating through all the combinations of settings for a
* single file:
*/
unsigned int tsp; /* nsp from the last run; this is the
* index+1 of the highest active entry on
* this run; this entry will be advanced.
*/
# define SL 8 /* stack limit */
struct stack
{
png_byte opt; /* The option being tested */
png_byte entry; /* The next value entry to be tested */
png_byte end; /* This is the last entry */
int opt_string_end; /* End of the option string in 'curr' */
} stack[SL]; /* Stack of entries being tested */
char curr[32*SL]; /* current options being tested */
char best[32*SL]; /* best options */
char namebuf[FILENAME_MAX+1]; /* output file name */
};
static void
display_init(struct display *dp)
/* Call this only once right at the start to initialize the control
* structure, the (struct buffer) lists are maintained across calls - the
* memory is not freed.
*/
{
memset(dp, 0, sizeof *dp);
dp->operation = "internal error";
dp->filename = "command line";
dp->output_file = "no output file";
dp->options = WARNINGS; /* default to !verbose, !quiet */
dp->fp = NULL;
dp->read_pp = NULL;
dp->ip = NULL;
dp->write_pp = NULL;
}
static void
display_clean_read(struct display *dp)
{
if (dp->read_pp != NULL)
png_destroy_read_struct(&dp->read_pp, NULL, NULL);
if (dp->fp != NULL)
{
FILE *fp = dp->fp;
dp->fp = NULL;
(void)fclose(fp);
}
}
static void
display_clean_write(struct display *dp)
{
if (dp->fp != NULL)
{
FILE *fp = dp->fp;
dp->fp = NULL;
(void)fclose(fp);
}
if (dp->write_pp != NULL)
png_destroy_write_struct(&dp->write_pp, dp->tsp > 0 ? NULL : &dp->ip);
}
static void
display_clean(struct display *dp)
{
display_clean_read(dp);
display_clean_write(dp);
dp->output_file = NULL;
/* leave the filename for error detection */
dp->results = 0; /* reset for next time */
}
static void
display_destroy(struct display *dp)
{
/* Release any memory held in the display. */
display_clean(dp);
}
static struct display *
get_dp(png_structp pp)
/* The display pointer is always stored in the png_struct error pointer */
{
struct display *dp = (struct display*)png_get_error_ptr(pp);
if (dp == NULL)
{
fprintf(stderr, "pngcp: internal error (no display)\n");
exit(99); /* prevents a crash */
}
return dp;
}
/* error handling */
#ifdef __GNUC__
# define VGATTR __attribute__((__format__ (__printf__,3,4)))
/* Required to quiet GNUC warnings when the compiler sees a stdarg function
* that calls one of the stdio v APIs.
*/
#else
# define VGATTR
#endif
static void VGATTR
display_log(struct display *dp, error_level level, const char *fmt, ...)
/* 'level' is as above, fmt is a stdio style format string. This routine
* does not return if level is above LIBPNG_WARNING
*/
{
dp->results |= 1U << level;
if (level > (error_level)(dp->options & LEVEL_MASK))
{
const char *lp;
va_list ap;
switch (level)
{
case INFORMATION: lp = "information"; break;
case LIBPNG_WARNING: lp = "warning(libpng)"; break;
case APP_WARNING: lp = "warning(pngcp)"; break;
case APP_FAIL: lp = "error(continuable)"; break;
case LIBPNG_ERROR: lp = "error(libpng)"; break;
case LIBPNG_BUG: lp = "bug(libpng)"; break;
case APP_ERROR: lp = "error(pngcp)"; break;
case USER_ERROR: lp = "error(user)"; break;
case INTERNAL_ERROR: /* anything unexpected is an internal error: */
case VERBOSE: case WARNINGS: case ERRORS: case QUIET:
default: lp = "bug(pngcp)"; break;
}
fprintf(stderr, "%s: %s: %s",
dp->filename != NULL ? dp->filename : "<stdin>", lp, dp->operation);
fprintf(stderr, ": ");
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
va_end(ap);
fputc('\n', stderr);
}
/* else do not output any message */
/* Errors cause this routine to exit to the fail code */
if (level > APP_FAIL || (level > ERRORS && !(dp->options & CONTINUE)))
{
if (dp->errset)
longjmp(dp->error_return, level);
else
exit(99);
}
}
/* OPTIONS:
*
* The command handles options of the forms:
*
* --option
* Turn an option on (Option)
* --no-option
* Turn an option off (Option)
* --option=value
* Set an option to a value (Value)
* --option=val1,val2,val3
* Set an option to a bitmask constructed from the values (List)
*/
static png_byte
optind(struct display *dp, const char *opt, size_t len)
/* Return the index (in options[]) of the given option, outputs an error if
* it does not exist. Takes the name of the option and a length (number of
* characters in the name).
*/
{
png_byte j;
for (j=0; j<opt_count; ++j)
if (strncmp(options[j].name, opt, len) == 0 && options[j].name[len] == 0)
return j;
/* If the setjmp buffer is set the code is asking for an option index; this
* is bad. Otherwise this is the command line option parsing.
*/
display_log(dp, dp->errset ? INTERNAL_ERROR : USER_ERROR,
"%.*s: unknown option", (int)/*SAFE*/len, opt);
abort(); /* NOT REACHED */
}
static int
getopt(struct display *dp, const char *opt, int *value)
{
const png_byte i = optind(dp, opt, strlen(opt));
if (dp->entry[i]) /* option was set on command line */
{
*value = dp->value[i];
return 1;
}
else
return 0;
}
static void
set_opt_string(struct display *dp, unsigned int sp)
/* Add the appropriate option string to dp->curr. */
{
int offset, add;
png_byte opt = dp->stack[sp].opt;
const char *entry_name = options[opt].values[dp->stack[sp].entry].name;
if (sp > 0)
offset = dp->stack[sp-1].opt_string_end;
else
offset = 0;
if (entry_name == range_lo)
add = sprintf(dp->curr+offset, " --%s=%d", options[opt].name,
dp->value[opt]);
else
add = sprintf(dp->curr+offset, " --%s=%s", options[opt].name, entry_name);
if (add < 0)
display_log(dp, INTERNAL_ERROR, "sprintf failed");
assert(offset+add < (int)/*SAFE*/sizeof dp->curr);
dp->stack[sp].opt_string_end = offset+add;
}
static int
opt_list_end(struct display *dp, png_byte opt, png_byte entry)
{
if (options[opt].values[entry].name == range_lo)
return entry+1U >= options[opt].value_count /* missing range_hi */ ||
options[opt].values[entry+1U].name != range_hi /* likewise */ ||
options[opt].values[entry+1U].value <= dp->value[opt] /* range end */;
else
return entry+1U >= options[opt].value_count /* missing 'all' */ ||
options[opt].values[entry+1U].name == all /* last entry */;
}
static void
push_opt(struct display *dp, unsigned int sp, png_byte opt)
/* Push a new option onto the stack, initializing the new stack entry
* appropriately; this does all the work of next_opt (setting end/nsp) for
* the first entry in the list.
*/
{
png_byte entry;
const char *entry_name;
assert(sp == dp->tsp && sp < SL);
/* The starting entry is entry 0 unless there is a range in which case it is
* the entry corresponding to range_lo:
*/
entry = options[opt].value_count;
assert(entry > 0U);
do
{
entry_name = options[opt].values[--entry].name;
if (entry_name == range_lo)
break;
}
while (entry > 0U);
dp->tsp = sp+1U;
dp->stack[sp].opt = opt;
dp->stack[sp].entry = entry;
dp->value[opt] = options[opt].values[entry].value;
set_opt_string(dp, sp);
if (opt_list_end(dp, opt, entry))
{
dp->stack[sp].end = 1;
display_log(dp, APP_WARNING, "%s: only testing one value",
options[opt].name);
}
else
{
dp->stack[sp].end = 0;
dp->nsp = dp->tsp;
}
}
static void
next_opt(struct display *dp, unsigned int sp)
/* Return the next value for this option. When called 'sp' is expected to be
* the topmost stack entry - only the topmost entry changes each time round -
* and there must be a valid entry to return. next_opt will set dp->nsp to
* sp+1 if more entries are available, otherwise it will not change it and
* set dp->stack[s].end to true.
*/
{
png_byte entry, opt;
const char *entry_name;
/* dp->stack[sp] must be the top stack entry and it must be active: */
assert(sp+1U == dp->tsp && !dp->stack[sp].end);
opt = dp->stack[sp].opt;
entry = dp->stack[sp].entry;
assert(entry+1U < options[opt].value_count);
entry_name = options[opt].values[entry].name;
assert(entry_name != NULL);
/* For ranges increment the value but don't change the entry, for all other
* cases move to the next entry and load its value:
*/
if (entry_name == range_lo) /* a range */
dp->value[opt]++;
else
{
/* Increment 'entry' */
dp->value[opt] = options[opt].values[++entry].value;
dp->stack[sp].entry = entry;
}
set_opt_string(dp, sp);
if (opt_list_end(dp, opt, entry)) /* end of list */
dp->stack[sp].end = 1;
else /* still active after all these tests */
dp->nsp = dp->tsp;
}
static int
getallopts(struct display *dp, const char *opt_str, int *value)
/* Like getop but iterate over all the values if the option was set to "all".
*/
{
const png_byte opt = optind(dp, opt_str, strlen(opt_str));
if (dp->entry[opt]) /* option was set on command line */
{
/* Simple, single value, entries don't have a stack frame and have a fixed
* value (it doesn't change once set on the command line). Otherwise the
* value (entry) selected from the command line is 'all':
*/
if (options[opt].values[dp->entry[opt]-1].name == all)
{
unsigned int sp = dp->csp++; /* my stack entry */
assert(sp >= dp->nsp); /* nsp starts off zero */
/* If the entry was active in the previous run dp->stack[sp] is already
* set up and dp->tsp will be greater than sp, otherwise a new entry
* needs to be created.
*
* dp->nsp is handled this way:
*
* 1) When an option is pushed onto the stack dp->nsp and dp->tsp are
* both set (by push_opt) to the next stack entry *unless* there is
* only one entry in the new list, in which case dp->stack[sp].end
* is set.
*
* 2) For the top stack entry next_opt is called. The entry must be
* active (dp->stack[sp].end is not set) and either 'nsp' or 'end'
* will be updated as appropriate.
*
* 3) For lower stack entries nsp is set unless the stack entry is
* already at the end. This means that when all the higher entries
* are popped this entry will be too.
*/
if (sp >= dp->tsp)
push_opt(dp, sp, opt); /* This sets tsp to sp+1 */
else if (sp+1U >= dp->tsp)
next_opt(dp, sp);
else if (!dp->stack[sp].end) /* Active, not at top of stack */
dp->nsp = sp+1U;
}
*value = dp->value[opt];
return 1; /* set */
}
else
return 0; /* not set */
}
static int
find_val(struct display *dp, png_byte opt, const char *str, size_t len)
/* Like optind but sets (index+i) of the entry in options[opt] that matches
* str[0..len-1] into dp->entry[opt] as well as returning the actual value.
*/
{
int rlo = INT_MAX, rhi = INT_MIN;
png_byte j, irange = 0;
for (j=1U; j<=options[opt].value_count; ++j)
{
if (strncmp(options[opt].values[j-1U].name, str, len) == 0 &&
options[opt].values[j-1U].name[len] == 0)
{
dp->entry[opt] = j;
return options[opt].values[j-1U].value;
}
else if (options[opt].values[j-1U].name == range_lo)
rlo = options[opt].values[j-1U].value, irange = j;
else if (options[opt].values[j-1U].name == range_hi)
rhi = options[opt].values[j-1U].value;
}
/* No match on the name, but there may be a range. */
if (irange > 0)
{
char *ep = NULL;
long l = strtol(str, &ep, 0);
if (ep == str+len && l >= rlo && l <= rhi)
{
dp->entry[opt] = irange; /* range_lo */
return (int)/*SAFE*/l;
}
}
display_log(dp, dp->errset ? INTERNAL_ERROR : USER_ERROR,
"%s: unknown value setting '%.*s'", options[opt].name,
(int)/*SAFE*/len, str);
abort(); /* NOT REACHED */
}
static int
opt_check(struct display *dp, const char *arg)
{
assert(dp->errset == 0);
if (arg != NULL && arg[0] == '-' && arg[1] == '-')
{
int i = 0, negate = (strncmp(arg+2, "no-", 3) == 0), val;
png_byte j;
if (negate)
arg += 5; /* --no- */
else
arg += 2; /* -- */
/* Find the length (expect arg\0 or arg=) */
while (arg[i] != 0 && arg[i] != '=') ++i;
/* So arg[0..i-1] is the argument name, this does not return if this isn't
* a valid option name.
*/
j = optind(dp, arg, i);
/* It matcheth an option; check the remainder. */
if (arg[i] == 0) /* no specified value, use the default */
{
val = options[j].values[negate].value;
dp->entry[j] = (png_byte)/*SAFE*/(negate + 1U);
}
else
{
const char *list = arg + (i+1);
/* Expect a single value here unless this is a list, in which case
* multiple values are combined.
*/
if (options[j].opt != LIST)
{
/* find_val sets 'dp->entry[j]' to a non-zero value: */
val = find_val(dp, j, list, strlen(list));
if (negate)
{
if (options[j].opt < OPTION)
val = !val;
else
{
display_log(dp, USER_ERROR,
"%.*s: option=arg cannot be negated", i, arg);
abort(); /* NOT REACHED */
}
}
}
else /* multiple options separated by ',' characters */
{
/* --no-option negates list values from the default, which should
* therefore be 'all'. Notice that if the option list is empty in
* this case nothing will be removed and therefore --no-option= is
* the same as --option.
*/
if (negate)
val = options[j].values[0].value;
else
val = 0;
while (*list != 0) /* allows option= which sets 0 */
{
/* A value is terminated by the end of the list or a ','
* character.
*/
int v, iv;
iv = 0; /* an index into 'list' */
while (list[++iv] != 0 && list[iv] != ',') {}
v = find_val(dp, j, list, iv);
if (negate)
val &= ~v;
else
val |= v;
list += iv;
if (*list != 0)
++list; /* skip the ',' */
}
}
}
/* 'val' is the new value, store it for use later and debugging: */
dp->value[j] = val;
if (options[j].opt < LEVEL_MASK)
{
/* The handling for error levels is to set the level. */
if (val) /* Set this level */
dp->options = (dp->options & ~LEVEL_MASK) | options[j].opt;
else
display_log(dp, USER_ERROR,
"%.*s: messages cannot be turned off individually; set a message level",
i, arg);
}
else if (options[j].opt < OPTION)
{
if (val)
dp->options |= options[j].opt;
else
dp->options &= ~options[j].opt;
}
return 1; /* this is an option */
}
else
return 0; /* not an option */
}
/* The following is used in main to verify that the final argument is a
* directory:
*/
static int
checkdir(const char *pathname)
{
struct stat buf;
return stat(pathname, &buf) == 0 && S_ISDIR(buf.st_mode);
}
/* Work out whether a path is valid (if not a display_log occurs), a directory
* (1 is returned) or a file *or* non-existent (0 is returned).
*
* Used for a write path.
*/
static int
isdir(struct display *dp, const char *pathname)
{
if (pathname == NULL)
return 0; /* stdout */
else if (pathname[0] == 0)
return 1; /* empty string */
else
{
struct stat buf;
int ret = stat(pathname, &buf);
if (ret == 0) /* the entry exists */
{
if (S_ISDIR(buf.st_mode))
return 1;
/* Else expect an object that exists and can be written: */
if (access(pathname, W_OK) != 0)
display_log(dp, USER_ERROR, "%s: cannot be written (%s)", pathname,
strerror(errno));
return 0; /* file (exists, can be written) */
}
else /* an error */
{
/* Non-existence is fine, other errors are not: */
if (errno != ENOENT)
display_log(dp, USER_ERROR, "%s: invalid output name (%s)",
pathname, strerror(errno));
return 0; /* file (does not exist) */
}
}
}
static void
makename(struct display *dp, const char *dir, const char *infile)
{
/* Make a name for an output file (and check it). */
dp->namebuf[0] = 0;
if (dir == NULL || infile == NULL)
display_log(dp, INTERNAL_ERROR, "NULL name to makename");
else
{
size_t dsize = strlen(dir);
if (dsize < FILENAME_MAX+2)
{
size_t isize = strlen(infile);
size_t istart = isize-1;
/* This should fail before here: */
if (infile[istart] == '/')
display_log(dp, INTERNAL_ERROR, "infile with trailing /");
memcpy(dp->namebuf, dir, dsize);
if (dsize > 0 && dp->namebuf[dsize-1] != '/')
dp->namebuf[dsize++] = '/';
/* Find the rightmost non-/ character: */
while (istart > 0 && infile[istart-1] != '/')
--istart;
isize -= istart;
infile += istart;
if (dsize+isize <= FILENAME_MAX)
{
memcpy(dp->namebuf+dsize, infile, isize+1);
if (isdir(dp, dp->namebuf))
display_log(dp, USER_ERROR, "%s: output file is a directory",
dp->namebuf);
}
else
{
dp->namebuf[dsize] = 0;
display_log(dp, USER_ERROR, "%s%s: output file name too long",
dp->namebuf, infile);
}
}
else
display_log(dp, USER_ERROR, "%s: output directory name too long", dir);
}
}
/* error handler callbacks for libpng */
static void PNGCBAPI
display_warning(png_structp pp, png_const_charp warning)
{
display_log(get_dp(pp), LIBPNG_WARNING, "%s", warning);
}
static void PNGCBAPI
display_error(png_structp pp, png_const_charp error)
{
struct display *dp = get_dp(pp);
display_log(dp, LIBPNG_ERROR, "%s", error);
}
static void
display_start_read(struct display *dp, const char *filename)
{
if (filename != NULL)
{
dp->filename = filename;
dp->fp = fopen(filename, "rb");
}
else
{
dp->filename = "<stdin>";
dp->fp = stdin;
}
dp->w = dp->h = 0U;
dp->bpp = 0U;
dp->size = 0U;
dp->read_size = 0U;
if (dp->fp == NULL)
display_log(dp, USER_ERROR, "file open failed (%s)", strerror(errno));
}
static void PNGCBAPI
read_function(png_structp pp, png_bytep data, png_size_t size)
{
struct display *dp = get_dp(pp);
if (fread(data, size, 1U, dp->fp) == 1U)
dp->read_size += size;
else
{
if (feof(dp->fp))
display_log(dp, USER_ERROR, "PNG file truncated");
else
display_log(dp, USER_ERROR, "PNG file read failed (%s)",
strerror(errno));
}
}
static void
read_png(struct display *dp, const char *filename)
{
display_clean_read(dp); /* safety */
display_start_read(dp, filename);
dp->read_pp = png_create_read_struct(PNG_LIBPNG_VER_STRING, dp,
display_error, display_warning);
if (dp->read_pp == NULL)
display_log(dp, LIBPNG_ERROR, "failed to create read struct");
/* The png_read_png API requires us to make the info struct, but it does the
* call to png_read_info.
*/
dp->ip = png_create_info_struct(dp->read_pp);
if (dp->ip == NULL)
display_log(dp, LIBPNG_ERROR, "failed to create info struct");
/* Set the IO handling */
png_set_read_fn(dp->read_pp, dp, read_function);
# ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
png_set_keep_unknown_chunks(dp->read_pp, PNG_HANDLE_CHUNK_ALWAYS, NULL,
0);
# endif /* SET_UNKNOWN_CHUNKS */
# ifdef PNG_SET_USER_LIMITS_SUPPORTED
/* Remove the user limits, if any */
png_set_user_limits(dp->read_pp, 0x7fffffff, 0x7fffffff);
# endif /* SET_USER_LIMITS */
/* Now read the PNG. */
png_read_png(dp->read_pp, dp->ip, 0U/*transforms*/, NULL/*params*/);
dp->w = png_get_image_width(dp->read_pp, dp->ip);
dp->h = png_get_image_height(dp->read_pp, dp->ip);
dp->bpp = png_get_bit_depth(dp->read_pp, dp->ip) *
png_get_channels(dp->read_pp, dp->ip);
dp->size = png_get_rowbytes(dp->read_pp, dp->ip) * dp->h; /* can overflow */
display_clean_read(dp);
dp->operation = "none";
}
static void
display_start_write(struct display *dp, const char *filename)
{
if (filename != NULL)
{
dp->output_file = filename;
dp->fp = fopen(filename, "wb");
}
else
{
dp->output_file = "<stdout>";
dp->fp = stdout;
}
dp->write_size = 0U;
if (dp->fp == NULL)
display_log(dp, USER_ERROR, "%s: file open failed (%s)", dp->output_file,
strerror(errno));
}
static void PNGCBAPI
write_function(png_structp pp, png_bytep data, png_size_t size)
{
struct display *dp = get_dp(pp);
if (fwrite(data, size, 1U, dp->fp) == 1U)
dp->write_size += size;
else
display_log(dp, USER_ERROR, "%s: PNG file write failed (%s)",
dp->output_file, strerror(errno));
}
/* Compression option, 'method' is never set: there is no choice */
#define SET_COMPRESSION\
SET(strategy, strategy);\
SET(level, level);\
SET(windowBits, window_bits);\
SET(memLevel, mem_level);
#ifdef PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED
static void
set_compression(struct display *dp)
{
int val;
# define SET(name, func) if (getallopts(dp, #name, &val))\
png_set_compression_ ## func(dp->write_pp, val);
SET_COMPRESSION
# undef SET
}
#else
# define set_compression(dp, pp) ((void)0)
#endif /* WRITE_CUSTOMIZE_COMPRESSION */
#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
static void
set_text_compression(struct display *dp)
{
int val;
# define SET(name, func) if (getallopts(dp, "text-" #name, &val))\
png_set_text_compression_ ## func(dp->write_pp, val);
SET_COMPRESSION
# undef SET
}
#else
# define set_text_compression(dp, pp) ((void)0)
#endif /* WRITE_CUSTOMIZE_ZTXT_COMPRESSION */
static void
write_png(struct display *dp, const char *destname)
{
display_clean_write(dp); /* safety */
display_start_write(dp, destname);
dp->write_pp = png_create_write_struct(PNG_LIBPNG_VER_STRING, dp,
display_error, display_warning);
if (dp->write_pp == NULL)
display_log(dp, APP_ERROR, "failed to create write png_struct");
png_set_write_fn(dp->write_pp, dp, write_function, NULL/*flush*/);
# ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
png_set_keep_unknown_chunks(dp->write_pp, PNG_HANDLE_CHUNK_ALWAYS, NULL,
0);
# endif /* SET_UNKNOWN_CHUNKS */
# ifdef PNG_SET_USER_LIMITS_SUPPORTED
/* Remove the user limits, if any */
png_set_user_limits(dp->write_pp, 0x7fffffff, 0x7fffffff);
# endif
/* OPTION HANDLING */
/* compression outputs, IDAT and zTXt/iTXt: */
dp->tsp = dp->nsp;
dp->nsp = dp->csp = 0;
set_compression(dp);
set_text_compression(dp);
/* filter handling */
#if defined(PNG_SELECT_FILTER_HEURISTICALLY_SUPPORTED) ||\
defined(PNG_SELECT_FILTER_METHODICALLY_SUPPORTED)
{
int val;
if (getopt(dp, "select", &val))
{
# ifdef PNG_SELECT_FILTER_HEURISTICALLY_SUPPORTED
png_set_option(dp->write_pp, PNG_SELECT_FILTER_HEURISTICALLY,
(val & SELECT_HEURISTICALLY) != 0);
# endif /* SELECT_FILTER_HEURISTICALLY */
# ifdef PNG_SELECT_FILTER_METHODICALLY_SUPPORTED
png_set_option(dp->write_pp, PNG_SELECT_FILTER_METHODICALLY,
(val & SELECT_METHODICALLY) != 0);
# endif /* SELECT_FILTER_METHODICALLY */
}
}
#endif /* SELECT_FILTER_HEURISTICALLY || SELECT_FILTER_METHODICALLY */
# ifdef PNG_WRITE_FILTER_SUPPORTED
{
int val;
if (getopt(dp, "filter", &val))
png_set_filter(dp->write_pp, PNG_FILTER_TYPE_BASE, val);
}
# endif /* WRITE_FILTER */
/* This just uses the 'read' info_struct directly, it contains the image. */
png_write_png(dp->write_pp, dp->ip, 0U/*transforms*/, NULL/*params*/);
/* Make sure the file was written ok: */
{
FILE *fp = dp->fp;
dp->fp = NULL;
if (fclose(fp))
display_log(dp, APP_ERROR, "%s: write failed (%s)", destname,
strerror(errno));
}
/* Clean it on the way out - if control returns to the caller then the
* written_file contains the required data.
*/
display_clean_write(dp);
dp->operation = "none";
}
static void
cp_one_file(struct display *dp, const char *filename, const char *destname)
{
dp->filename = filename;
dp->operation = "read";
/* Read it then write it: */
if (filename != NULL && access(filename, R_OK) != 0)
display_log(dp, USER_ERROR, "%s: invalid file name (%s)",
filename, strerror(errno));
read_png(dp, filename);
/* But 'destname' may be a directory. */
dp->operation = "write";
if (destname != NULL) /* else stdout */
{
if (isdir(dp, destname))
{
makename(dp, destname, filename);
destname = dp->namebuf;
}
else if (access(destname, W_OK) != 0 && errno != ENOENT)
display_log(dp, USER_ERROR, "%s: invalid output name (%s)", destname,
strerror(errno));
}
dp->nsp = 0;
dp->curr[0] = 0;
dp->best[0] = 0; /* acts as a flag for the caller */
write_png(dp, destname);
if (dp->nsp > 0) /* interating over lists */
{
char tmpname[(sizeof dp->namebuf) + 4];
assert(dp->curr[0] == ' ' && dp->tsp > 0);
/* Loop to find the best option, first initialize the 'best' fields: */
strcpy(dp->best, dp->curr);
dp->best_size = dp->write_size;
strcpy(tmpname, destname);
strcat(tmpname, ".tmp"); /* space for .tmp allocated above */
do
{
write_png(dp, tmpname);
/* And compare the sizes (theoretically this could overflow, in which
* case this program will need to be rewritten perhaps considerably).
*/
if (dp->write_size < dp->best_size)
{
if (rename(tmpname, destname) != 0)
display_log(dp, APP_ERROR, "rename %s %s failed (%s)", tmpname,
destname, strerror(errno));
strcpy(dp->best, dp->curr);
dp->best_size = dp->write_size;
}
else if (unlink(tmpname) != 0)
display_log(dp, APP_WARNING, "unlink %s failed (%s)", tmpname,
strerror(errno));
}
while (dp->nsp > 0);
/* Do this for the 'sizes' option so that it reports the correct size. */
dp->write_size = dp->best_size;
}
}
static int
cppng(struct display *dp, const char *file, const char *gv dest)
/* Exists solely to isolate the setjmp clobbers which some versions of GCC
* erroneously generate.
*/
{
int ret = setjmp(dp->error_return);
if (ret == 0)
{
dp->errset = 1;
cp_one_file(dp, file, dest);
dp->errset = 0;
return 0;
}
else
{
dp->errset = 0;
if (ret < ERRORS) /* shouldn't longjmp on warnings */
display_log(dp, INTERNAL_ERROR, "unexpected return code %d", ret);
return ret;
}
}
int
main(const int argc, const char * const * const argv)
{
/* For each file on the command line test it with a range of transforms */
int option_end;
struct display d;
display_init(&d);
d.operation = "options";
for (option_end = 1;
option_end < argc && opt_check(&d, argv[option_end]);
++option_end)
{
}
/* Do a quick check on the directory target case; when there are more than
* two arguments the last one must be a directory.
*/
if (option_end+2 < argc && !checkdir(argv[argc-1]))
{
fprintf(stderr,
"pngcp: %s: directory required with more than two arguments\n",
argv[argc-1]);
return 99;
}
{
int errors = 0;
int i = option_end;
/* Do this at least once; if there are no arguments stdin/stdout are used.
*/
d.operation = "files";
do
{
const char *infile = NULL;
const char *outfile = NULL;
if (i < argc)
{
infile = argv[i++];
if (i < argc)
outfile = argv[argc-1];
}
{
int ret = cppng(&d, infile, outfile);
if (ret > QUIET) /* abort on user or internal error */
return 99;
}
if (d.options & SIZES)
printf("%s [%ld x %ld %d bpp %lu bytes] 0x%lx %lu -> %lu\n",
infile, (unsigned long)d.w, (unsigned long)d.h, d.bpp,
(unsigned long)d.size, (unsigned long)d.results,
(unsigned long)d.read_size, (unsigned long)d.write_size);
/* This somewhat replicates the above information, but it seems better
* to do both.
*/
if (d.best[0] != 0 && (error_level)(d.options & LEVEL_MASK) < QUIET)
printf("%s [%ld x %ld %d bpp %lu bytes] %lu -> %lu with '%s'\n",
infile, (unsigned long)d.w, (unsigned long)d.h, d.bpp,
(unsigned long)d.size, (unsigned long)d.read_size,
(unsigned long)d.best_size, d.best);
/* Here on any return, including failures, except user/internal issues
*/
{
const int pass = (d.options & STRICT) ?
RESULT_STRICT(d.results) : RESULT_RELAXED(d.results);
if (!pass)
++errors;
if (d.options & LOG)
{
int j;
printf("%s: pngcp", pass ? "PASS" : "FAIL");
for (j=1; j<option_end; ++j)
printf(" %s", argv[j]);
if (infile != NULL)
printf(" %s", infile);
printf("\n");
}
}
display_clean(&d);
}
while (i+1 < argc);
/* I.e. for all cases after the first time through the loop require
* there to be at least two arguments left and for the last one to be a
* directory (this was checked above).
*/
/* Release allocated memory */
display_destroy(&d);
return errors != 0;
}
}
#else /* !READ_PNG || !WRITE_PNG */
int
main(void)
{
fprintf(stderr, "pngcp: no support for png_read/write_image\n");
return 77;
}
#endif