/*
- * Copyright (C) 2003-2010 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2003-2011 Andre Noll <maan@tuebingen.mpg.de>
*
* Licensed under the GPL v2. For licencing details see COPYING.
*/
/** \file exec.c Helper functions for spawning new processes. */
#include <string.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
#include <unistd.h>
#include <assert.h>
#include <stdlib.h>
#include <signal.h>
-
+#include <errno.h>
#include "gcc-compat.h"
#include "log.h"
-#include "error.h"
-#include "string.h"
-
+#include "err.h"
+#include "str.h"
+#include "exec.h"
/**
- * Spawn a new process and redirect fd 0, 1, and 2.
+ * Spawn a new process using execvp().
*
* \param pid Will hold the pid of the created process upon return.
* \param file Path of the executable to execute.
* \param args The argument array for the command.
- * \param fds a Pointer to a value-result array.
*
* \return Standard.
*
- * \sa null(4), pipe(2), dup2(2), fork(2), exec(3).
+ * \sa fork(2), exec(3).
*/
-int dss_exec(pid_t *pid, const char *file, char *const *const args, int *fds)
+void dss_exec(pid_t *pid, const char *file, char *const *const args)
{
- int ret, in[2] = {-1, -1}, out[2] = {-1, -1}, err[2] = {-1, -1},
- null = -1; /* ;) */
-
- ret = -E_DUP_PIPE;
- if (fds[0] > 0 && pipe(in) < 0)
- goto err_out;
- if (fds[1] > 0 && pipe(out) < 0)
- goto err_out;
- if (fds[2] > 0 && pipe(err) < 0)
- goto err_out;
- if (!fds[0] || !fds[1] || !fds[2]) {
- ret = -E_NULL_OPEN;
- null = open("/dev/null", O_RDWR);
- if (null < 0)
- goto err_out;
- }
- if ((*pid = fork()) < 0)
+ if ((*pid = fork()) < 0) {
+ DSS_EMERG_LOG(("fork error: %s\n", strerror(errno)));
exit(EXIT_FAILURE);
- if (!(*pid)) { /* child */
- if (fds[0] >= 0) {
- if (fds[0]) {
- close(in[1]);
- if (in[0] != STDIN_FILENO)
- dup2(in[0], STDIN_FILENO);
- } else
- dup2(null, STDIN_FILENO);
- }
- if (fds[1] >= 0) {
- if (fds[1]) {
- close(out[0]);
- if (out[1] != STDOUT_FILENO)
- dup2(out[1], STDOUT_FILENO);
- } else
- dup2(null, STDOUT_FILENO);
- }
- if (fds[2] >= 0) {
- if (fds[2]) {
- close(err[0]);
- if (err[1] != STDERR_FILENO)
- dup2(err[1], STDERR_FILENO);
- } else
- dup2(null, STDERR_FILENO);
- }
- if (null >= 0)
- close(null);
- signal(SIGINT, SIG_DFL);
- signal(SIGTERM, SIG_DFL);
- signal(SIGCHLD, SIG_DFL);
- execvp(file, args);
- _exit(EXIT_FAILURE);
- }
- if (fds[0] > 0) {
- close(in[0]);
- *fds = in[1];
- }
- if (fds[1] > 0) {
- close(out[1]);
- *(fds + 1) = out[0];
- }
- if (fds[2] > 0) {
- close(err[1]);
- *(fds + 2) = err[0];
}
- if (null >= 0)
- close(null);
- return 1;
-err_out:
- DSS_ERROR_LOG("failed to exec %s\n", file);
- if (err[0] >= 0)
- close(err[0]);
- if (err[1] >= 0)
- close(err[1]);
- if (out[0] >= 0)
- close(out[0]);
- if (out[1] >= 0)
- close(out[1]);
- if (in[0] >= 0)
- close(in[0]);
- if (in[1] >= 0)
- close(in[1]);
- if (null >= 0)
- close(null);
- return ret;
+ if (*pid) /* parent */
+ return;
+ signal(SIGINT, SIG_DFL);
+ signal(SIGTERM, SIG_DFL);
+ signal(SIGCHLD, SIG_DFL);
+ execvp(file, args);
+ DSS_EMERG_LOG(("execvp error: %s\n", strerror(errno)));
+ _exit(EXIT_FAILURE);
}
-
/**
- * Exec the given command.
+ * Exec the command given as a command line.
*
* \param pid Will hold the pid of the created process upon return.
- * \param cmdline Holds the command and its arguments, seperated by spaces.
- * \param fds A pointer to a value-result array.
- *
- * This function uses fork/exec to create a new process. \a fds must be a
- * pointer to three integers, corresponding to stdin, stdout and stderr
- * respectively. It specifies how to deal with fd 0, 1, 2 in the child. The
- * contents of \a fds are interpreted as follows:
- *
- * - fd[i] < 0: leave fd \a i alone.
- * - fd[i] = 0: dup fd \a i to \p /dev/null.
- * - fd[i] > 0: create a pipe and dup i to one end of that pipe.
- * Upon return, fd[i] contains the file descriptor of the pipe.
+ * \param cmdline Holds the command and its arguments, separated by spaces.
*
- * In any case, all unneeded filedescriptors are closed.
+ * This function uses fork/exec to create a new process.
*
* \return Standard.
*/
-int dss_exec_cmdline_pid(pid_t *pid, const char *cmdline, int *fds)
+void dss_exec_cmdline_pid(pid_t *pid, const char *cmdline)
{
- int argc, ret;
- char **argv;
- char *tmp = dss_strdup(cmdline);
+ char **argv, *tmp = dss_strdup(cmdline);
- if (!tmp)
- exit(EXIT_FAILURE);
- argc = split_args(tmp, &argv, " \t");
- ret = dss_exec(pid, argv[0], argv, fds);
+ split_args(tmp, &argv, " \t");
+ dss_exec(pid, argv[0], argv);
free(argv);
free(tmp);
- return ret;
}
-
-