static Bool
readPngFileToImage (FILE *file,
int *width,
int *height,
void **data)
{
unsigned char png_sig[PNG_SIG_SIZE];
int sig_bytes;
png_struct *png;
png_info *info;
Bool status;
sig_bytes = fread (png_sig, 1, PNG_SIG_SIZE, file);
if (png_check_sig (png_sig, sig_bytes) == 0)
return FALSE;
png = png_create_read_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (!png)
return FALSE;
info = png_create_info_struct (png);
if (!info)
{
png_destroy_read_struct (&png, NULL, NULL);
return FALSE;
}
png_init_io (png, file);
png_set_sig_bytes (png, sig_bytes);
status = readPngData (png, info, data, width, height);
png_destroy_read_struct (&png, &info, NULL);
return status;
}
static Bool
readPngBuffer (const unsigned char *buffer,
char **data,
unsigned int *width,
unsigned int *height)
{
unsigned char png_sig[PNG_SIG_SIZE];
png_struct *png;
png_info *info;
const unsigned char *b = buffer + PNG_SIG_SIZE;
Bool status;
memcpy (png_sig, buffer, PNG_SIG_SIZE);
if (png_check_sig (png_sig, PNG_SIG_SIZE) == 0)
return FALSE;
png = png_create_read_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (!png)
return FALSE;
info = png_create_info_struct (png);
if (!info)
{
png_destroy_read_struct (&png, NULL, NULL);
return FALSE;
}
png_set_read_fn (png, (void *) &b, userReadData);
png_set_sig_bytes (png, PNG_SIG_SIZE);
status = readPngData (png, info, data, width, height);
png_destroy_read_struct (&png, &info, NULL);
return status;
}
bool
PngScreen::readPng (std::ifstream &file,
CompSize &size,
void *&data)
{
unsigned char png_sig[PNG_SIG_SIZE];
png_struct *png;
png_info *info;
bool status;
file.read ((char *) png_sig, PNG_SIG_SIZE);
if (file.fail ())
return false;
if (png_sig_cmp (png_sig, 0, PNG_SIG_SIZE) != 0)
return false;
png = png_create_read_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (!png)
return false;
info = png_create_info_struct (png);
if (!info)
{
png_destroy_read_struct (&png, NULL, NULL);
return false;
}
png_set_read_fn (png, &file, stdioReadFunc);
png_set_sig_bytes (png, PNG_SIG_SIZE);
status = readPngData (png, info, data, size);
png_destroy_read_struct (&png, &info, NULL);
return status;
}
