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/* See LICENSE file for copyright and license details. */
#include "arg.h"
#include "util.h"
#include <sys/wait.h>
#include <string.h>
#include <unistd.h>
static char *
xmemmem(char *h, const char *n, size_t hn, size_t nn)
{
char *p, *end;
if (nn > hn)
return NULL;
end = h + (hn - nn + 1);
for (p = h; p != end; p++) {
p = memchr(p, *n, (size_t)(end - p));
if (!p)
return NULL;
if (!memcmp(p, n, nn))
return p;
}
return NULL;
}
static void
usage(void)
{
eprintf("usage: %s\n", argv0);
}
int
main(int argc, char *argv[])
{
int pipe_rw[2];
int i, old_fd;
pid_t pid;
int status;
char buf[8096];
size_t ptr, n;
char *p;
ssize_t r;
ARGBEGIN {
default:
usage();
} ARGEND;
if (argc)
usage();
if (pipe(pipe_rw))
eprintf("pipe:");
if (pipe_rw[0] == STDIN_FILENO || pipe_rw[1] == STDIN_FILENO)
eprintf("no stdin open\n");
if (pipe_rw[0] == STDOUT_FILENO || pipe_rw[1] == STDOUT_FILENO)
eprintf("no stdout open\n");
for (i = 0; i < 2; i++) {
if (pipe_rw[i] == STDERR_FILENO) {
pipe_rw[i] = dup(old_fd = pipe_rw[i]);
if (pipe_rw[i] < 0)
eprintf("dup:");
close(old_fd);
}
}
pid = fork();
if (pid < 0)
eprintf("fork:");
if (!pid) {
close(pipe_rw[0]);
if (dup2(pipe_rw[1], STDOUT_FILENO) < 0)
eprintf("dup2:");
close(pipe_rw[1]);
execlp("convert", "convert", "-", "-depth", "8", "-alpha", "activate", "pam:-", NULL);
eprintf("exec convert:");
}
close(pipe_rw[1]);
for (ptr = 0;;) {
r = read(pipe_rw[0], buf + ptr, sizeof(buf) - ptr);
if (r < 0)
eprintf("read <subprocess>:");
if (r == 0)
break;
ptr += (size_t)r;
p = xmemmem(buf, "\nENDHDR\n", ptr, sizeof("\nENDHDR\n") - 1);
if (!p)
continue;
p += sizeof("\nENDHDR\n") - 1;
n = (size_t)(p - buf);
memmove(buf, buf + n, ptr - n);
n = ptr - n;
break;
}
for (;;) {
for (ptr = 0; ptr < n;) {
r = write(STDOUT_FILENO, buf + ptr, n - ptr);
if (r < 0)
eprintf("write <stdout>:");
ptr += (size_t)r;
}
r = read(pipe_rw[0], buf, sizeof(buf));
if (r < 0)
eprintf("read <subprocess>:");
if (r == 0)
break;
n = (size_t)r;
}
while (waitpid(pid, &status, 0) != pid);
return !!status;
}
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