1 /* 2 * Copyright (c) 1998, 1999 Kungliga Tekniska H�gskolan 3 * (Royal Institute of Technology, Stockholm, Sweden). 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * 3. Neither the name of the Institute nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifdef HAVE_CONFIG_H 35 #include <config.h> 36 RCSID("$Id: simple_exec.c,v 1.6 1999/12/02 16:58:52 joda Exp $"); 37 #endif 38 39 #include <stdarg.h> 40 #include <stdlib.h> 41 #ifdef HAVE_SYS_TYPES_H 42 #include <sys/types.h> 43 #endif 44 #ifdef HAVE_SYS_WAIT_H 45 #include <sys/wait.h> 46 #endif 47 #ifdef HAVE_UNISTD_H 48 #include <unistd.h> 49 #endif 50 #include <errno.h> 51 52 #include <roken.h> 53 54 #define EX_NOEXEC 126 55 #define EX_NOTFOUND 127 56 57 /* return values: 58 -1 on `unspecified' system errors 59 -2 on fork failures 60 -3 on waitpid errors 61 0- is return value from subprocess 62 126 if the program couldn't be executed 63 127 if the program couldn't be found 64 128- is 128 + signal that killed subprocess 65 */ 66 67 static int 68 check_status(pid_t pid) 69 { 70 while(1) { 71 int status; 72 73 while(waitpid(pid, &status, 0) < 0) 74 if (errno != EINTR) 75 return -3; 76 if(WIFSTOPPED(status)) 77 continue; 78 if(WIFEXITED(status)) 79 return WEXITSTATUS(status); 80 if(WIFSIGNALED(status)) 81 return WTERMSIG(status) + 128; 82 } 83 } 84 85 int 86 simple_execvp(const char *file, char *const args[]) 87 { 88 pid_t pid = fork(); 89 switch(pid){ 90 case -1: 91 return -2; 92 case 0: 93 execvp(file, args); 94 exit((errno == ENOENT) ? EX_NOTFOUND : EX_NOEXEC); 95 default: 96 return check_status(pid); 97 } 98 } 99 100 /* gee, I'd like a execvpe */ 101 int 102 simple_execve(const char *file, char *const args[], char *const envp[]) 103 { 104 pid_t pid = fork(); 105 switch(pid){ 106 case -1: 107 return -2; 108 case 0: 109 execve(file, args, envp); 110 exit((errno == ENOENT) ? EX_NOTFOUND : EX_NOEXEC); 111 default: 112 return check_status(pid); 113 } 114 } 115 116 static char ** 117 collect_args(va_list *ap) 118 { 119 char **argv = NULL; 120 int argc = 0, i = 0; 121 do { 122 if(i == argc) { 123 /* realloc argv */ 124 char **tmp = realloc(argv, (argc + 5) * sizeof(*argv)); 125 if(tmp == NULL) { 126 errno = ENOMEM; 127 return NULL; 128 } 129 argv = tmp; 130 argc += 5; 131 } 132 argv[i++] = va_arg(*ap, char*); 133 } while(argv[i - 1] != NULL); 134 return argv; 135 } 136 137 int 138 simple_execlp(const char *file, ...) 139 { 140 va_list ap; 141 char **argv; 142 int ret; 143 144 va_start(ap, file); 145 argv = collect_args(&ap); 146 va_end(ap); 147 if(argv == NULL) 148 return -1; 149 ret = simple_execvp(file, argv); 150 free(argv); 151 return ret; 152 } 153 154 int 155 simple_execle(const char *file, ... /* ,char *const envp[] */) 156 { 157 va_list ap; 158 char **argv; 159 char *const* envp; 160 int ret; 161 162 va_start(ap, file); 163 argv = collect_args(&ap); 164 envp = va_arg(ap, char **); 165 va_end(ap); 166 if(argv == NULL) 167 return -1; 168 ret = simple_execve(file, argv, envp); 169 free(argv); 170 return ret; 171 } 172