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#include "process.h"
#include "file.h"
#include "log.h"
#include <fcntl.h>
#include <stdlib.h>
#include <sys/wait.h>
#include <unistd.h>
static int exec_child(const char *args[])
{
int ret = execv(args[0], (char *const *)args);
if (ret < 0) {
print_errno("execv");
return ret;
}
return ret;
}
static int wait_for_child(pid_t pid, int *ec)
{
int status;
pid_t ret = waitpid(pid, &status, 0);
if (ret < 0) {
print_errno("waitpid");
return ret;
}
if (WIFEXITED(status))
*ec = WEXITSTATUS(status);
else
*ec = -1;
return 0;
}
int proc_spawn(const char *args[], int *ec)
{
pid_t child_pid = fork();
if (child_pid < 0) {
print_errno("fork");
return child_pid;
}
if (!child_pid)
exit(exec_child(args));
return wait_for_child(child_pid, ec);
}
static int redirect_and_exec_child(int pipe_fds[2], const char *args[])
{
int ret = 0;
check_errno(close(pipe_fds[0]), "close");
ret = dup2(pipe_fds[1], STDOUT_FILENO);
if (ret < 0) {
print_errno("dup2");
return ret;
}
ret = dup2(pipe_fds[1], STDERR_FILENO);
if (ret < 0) {
print_errno("dup2");
return ret;
}
return exec_child(args);
}
int proc_capture(const char *args[], struct proc_output *result)
{
int pipe_fds[2];
int ret = 0;
ret = pipe2(pipe_fds, O_CLOEXEC);
if (ret < 0) {
print_errno("pipe2");
return -1;
}
pid_t child_pid = fork();
if (child_pid < 0) {
print_errno("fork");
goto close_pipe;
}
if (!child_pid)
exit(redirect_and_exec_child(pipe_fds, args));
check_errno(close(pipe_fds[1]), "close");
ret = file_read(pipe_fds[0], &result->output, &result->output_len);
if (ret < 0)
goto close_pipe;
ret = wait_for_child(child_pid, &result->ec);
if (ret < 0)
goto free_output;
goto close_pipe;
free_output:
free(result->output);
close_pipe:
check_errno(close(pipe_fds[0]), "close");
/* No errno checking here, we might've already closed the write end. */
close(pipe_fds[1]);
return ret;
}
void proc_output_free(const struct proc_output *output)
{
free(output->output);
}
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