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#include "config.h"
#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <sys/time.h>
#include "popen3.h"
static void close_pipe(int fds[2])
{
if(fds[0] != -1) {
close(fds[0]);
fds[0] = -1;
}
if(fds[1] != -1) {
close(fds[1]);
fds[1] = -1;
}
}
pid_t popen3(char *const *command,
FILE **finptr,
FILE **foutptr,
FILE **ferrptr)
{
int err = 0;
int fdin[] = { -1, -1 };
int fdout[] = { -1, -1 };
int fderr[] = { -1, -1 };
int fdsig[] = { -1, -1 };
FILE *fin, *fout, *ferr;
pid_t pid;
ssize_t discard;
if(command == NULL || *command == NULL) {
errno = EINVAL;
return -1;
}
fin = fout = ferr = NULL;
if(finptr != NULL && (pipe(fdin) == -1 ||
(fin = fdopen(fdin[1], "w")) == NULL))
{
goto error;
}
if(foutptr != NULL && (pipe(fdout) == -1 ||
(fout = fdopen(fdout[0], "r")) == NULL))
{
goto error;
}
if(ferrptr != NULL && (pipe(fderr) == -1 ||
(ferr = fdopen(fderr[0], "r")) == NULL))
{
goto error;
}
if(pipe(fdsig) == -1 ||
fcntl(fdsig[0], F_SETFD, FD_CLOEXEC) == -1 ||
fcntl(fdsig[1], F_SETFD, FD_CLOEXEC) == -1)
{
goto error;
}
pid = fork();
switch(pid) {
case -1: /* error */
goto error;
case 0: /* child */
if(ferrptr != NULL) {
if(dup2(fderr[1], 2) == -1) {
goto error_dup2;
}
close_pipe(fderr);
} else {
close(2);
}
if(foutptr != NULL) {
if(dup2(fdout[1], 1) == -1) {
goto error_dup2;
}
close_pipe(fdout);
} else {
close(1);
}
if(finptr != NULL) {
if(dup2(fdin[0], 0) == -1) {
goto error_dup2;
}
close_pipe(fdin);
} else {
close(0);
}
execvp(*command, command);
error_dup2:
err = errno;
close(fdsig[0]);
discard = write(fdsig[1], &err, sizeof(err));
(void)discard;
close(fdsig[1]);
exit(-1);
default: /* parent */
{
/* wait for signal pipe to close */
int ret;
fd_set rfds;
close(fdsig[1]);
fdsig[1] = -1;
do {
FD_ZERO(&rfds);
FD_SET(fdsig[0], &rfds);
ret = select(fdsig[0] + 1, &rfds, NULL, NULL, NULL);
} while(ret == -1 && errno == EINTR);
if(ret == -1) {
goto error;
}
if((ret = read(fdsig[0], &err, sizeof(err))) != 0) {
if(ret != -1) {
assert(ret == sizeof(err));
errno = err;
}
goto error;
}
close(fdsig[0]);
fdsig[0] = -1;
}
break;
}
if(finptr != NULL) {
close(fdin[0]);
*finptr = fin;
}
if(foutptr != NULL) {
close(fdout[1]);
*foutptr = fout;
}
if(ferrptr != NULL) {
close(fderr[1]);
*ferrptr = ferr;
}
return pid;
error:
err = errno;
if(fin != NULL) {
fclose(fin);
fdin[1] = -1;
}
if(fout != NULL) {
fclose(fout);
fdout[0] = -1;
}
if(ferr != NULL) {
fclose(ferr);
fderr[0] = -1;
}
close_pipe(fdin);
close_pipe(fdout);
close_pipe(fderr);
close_pipe(fdsig);
errno = err;
return -1;
}
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