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/* Test stream*u.
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif /*HAVE_UNISTD_H*/
#include <string.h>
#include <vips/vips.h>
typedef struct _MyInput {
const char *filename;
unsigned char *contents;
size_t length;
size_t read_position;
} MyInput;
typedef struct _MyOutput {
const char *filename;
int fd;
} MyOutput;
static gint64
read_cb(VipsSourceCustom *source_custom,
void *buffer, gint64 length, MyInput *my_input)
{
gint64 bytes_read = VIPS_MIN(length,
my_input->length - my_input->read_position);
/*
printf("read_cb: buffer = 0x%p, length = %zd\n", buffer, length);
*/
memcpy(buffer,
my_input->contents + my_input->read_position, bytes_read);
my_input->read_position += bytes_read;
return bytes_read;
}
static gint64
seek_cb(VipsSourceCustom *source_custom,
gint64 offset, int whence, MyInput *my_input)
{
gint64 new_pos;
/*
printf("seek_cb: offset = %zd, whence = %d\n", offset, whence);
*/
switch (whence) {
case SEEK_SET:
new_pos = offset;
break;
case SEEK_CUR:
new_pos = my_input->read_position + offset;
break;
case SEEK_END:
new_pos = my_input->length + offset;
break;
default:
vips_error("demo", "%s", "bad 'whence'");
return -1;
}
my_input->read_position = VIPS_CLIP(0, new_pos, my_input->length);
return my_input->read_position;
}
static gint64
write_cb(VipsTargetCustom *target_custom,
const void *data, gint64 length, MyOutput *my_output)
{
gint64 bytes_written;
/*
printf("write_cb: data = 0x%p, length = %zd\n", data, length);
*/
bytes_written = write(my_output->fd, data, length);
return bytes_written;
}
static void
finish_cb(VipsTargetCustom *target_custom, MyOutput *my_output)
{
/*
printf("finish_cb:\n");
*/
close(my_output->fd);
my_output->fd = -1;
}
int
main(int argc, char **argv)
{
MyInput my_input;
MyOutput my_output;
VipsSourceCustom *source_custom;
VipsTargetCustom *target_custom;
VipsImage *image;
if (VIPS_INIT(argv[0]))
return -1;
if (argc != 3)
vips_error_exit("usage: %s in-file out-file.png", argv[0]);
my_input.filename = argv[1];
my_input.contents = NULL;
my_input.length = 0;
my_input.read_position = 0;
if (!g_file_get_contents(my_input.filename,
(char **) &my_input.contents, &my_input.length, NULL))
vips_error_exit("unable to load from %s", my_input.filename);
source_custom = vips_source_custom_new();
g_signal_connect(source_custom, "seek",
G_CALLBACK(seek_cb), &my_input);
g_signal_connect(source_custom, "read",
G_CALLBACK(read_cb), &my_input);
if (!(image = vips_image_new_from_source(
VIPS_SOURCE(source_custom), "",
"access", VIPS_ACCESS_SEQUENTIAL,
NULL)))
vips_error_exit(NULL);
my_output.filename = argv[2];
my_output.fd = -1;
if ((my_output.fd = vips__open(my_output.filename,
O_WRONLY | O_CREAT | O_TRUNC, 0644)) == -1)
vips_error_exit("unable to save to %s", my_output.filename);
target_custom = vips_target_custom_new();
g_signal_connect(target_custom, "write",
G_CALLBACK(write_cb), &my_output);
g_signal_connect(target_custom, "finish",
G_CALLBACK(finish_cb), &my_output);
if (vips_image_write_to_target(image, ".png",
VIPS_TARGET(target_custom), NULL))
vips_error_exit(NULL);
VIPS_UNREF(image);
VIPS_UNREF(source_custom);
VIPS_UNREF(target_custom);
g_free(my_input.contents);
return 0;
}
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