Simple fork+exec system() replacement.

git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@4607 ec53bebd-3082-4978-b11e-865c3cabbd6b
1998-03-19 19:41:19 +00:00
parent 820786812b
commit abbc3b68d5
1 changed files with 121 additions and 0 deletions
--- a/lib/roken/simple_exec.c
+++ b/lib/roken/simple_exec.c
@@ -0,0 +1,121 @@
+/*
+ * Copyright (c) 1998 Kungliga Tekniska H<>gskolan
+ * (Royal Institute of Technology, Stockholm, Sweden). 
+ * All rights reserved. 
+ *
+ * Redistribution and use in source and binary forms, with or without 
+ * modification, are permitted provided that the following conditions 
+ * are met: 
+ *
+ * 1. Redistributions of source code must retain the above copyright 
+ *    notice, this list of conditions and the following disclaimer. 
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright 
+ *    notice, this list of conditions and the following disclaimer in the 
+ *    documentation and/or other materials provided with the distribution. 
+ *
+ * 3. All advertising materials mentioning features or use of this software 
+ *    must display the following acknowledgement: 
+ *      This product includes software developed by Kungliga Tekniska 
+ *      H<>gskolan and its contributors. 
+ *
+ * 4. Neither the name of the Institute nor the names of its contributors 
+ *    may be used to endorse or promote products derived from this software 
+ *    without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 
+ * SUCH DAMAGE. 
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+RCSID("$Id$");
+#endif
+
+#include <stdarg.h>
+#include <stdlib.h>
+#ifdef HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+#ifdef HAVE_SYS_WAIT_H
+#include <sys/wait.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#include <errno.h>
+
+#define EX_NOEXEC	126
+#define EX_NOTFOUND	127
+
+/* return values:
+   -1   on `unspecified' system errors
+   -2   on fork failures
+   -3   on waitpid errors
+   0-   is return value from subprocess
+   126  if the program couldn't be executed
+   127  if the program couldn't be found
+   128- is 128 + signal that killed subprocess
+   */
+
+int
+simple_execvp(const char *file, char *const args[])
+{
+    pid_t pid = fork();
+    switch(pid){
+    case -1:
+	return -2;
+    case 0:
+	execvp(file, args);
+	exit((errno == ENOENT) ? EX_NOTFOUND : EX_NOEXEC);
+    default: 
+	while(1) {
+	    int status;
+	    if(waitpid(pid, &status, 0) < 0) {
+		return -3;
+	    }
+	    if(WIFSTOPPED(status))
+		continue;
+	    if(WIFEXITED(status))
+		return WEXITSTATUS(status);
+	    if(WIFSIGNALED(status))
+		return WTERMSIG(status) + 128;
+	}
+    }
+}
+
+int
+simple_execlp(const char *file, ...)
+{
+    va_list ap;
+    char **argv;
+    int argc, i;
+
+    argc = i = 0;
+    va_start(ap, file);
+    do {
+	if(i == argc) {
+	    char **tmp = realloc(argv, (argc + 5) * sizeof(*argv));
+	    if(tmp == NULL) {
+		errno = ENOMEM;
+		return -1;
+	    }
+	    argv = tmp;
+	    argc += 5;
+	}
+	argv[i++] = va_arg(ap, char*);
+    } while(argv[i - 1] != NULL);
+    va_end(ap);
+    i = simple_execvp(file, argv);
+    free(argv);
+    return i;
+}