| 1 | /* Copyright (C) 1995, 1996, 1997, 1998, 2000, 2001, 2003, 2004, 2009, |
| 2 | * 2010, 2012, 2013, 2014 Free Software Foundation, Inc. |
| 3 | * |
| 4 | * This library is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU Lesser General Public License |
| 6 | * as published by the Free Software Foundation; either version 3 of |
| 7 | * the License, or (at your option) any later version. |
| 8 | * |
| 9 | * This library is distributed in the hope that it will be useful, but |
| 10 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | * Lesser General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU Lesser General Public |
| 15 | * License along with this library; if not, write to the Free Software |
| 16 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 17 | * 02110-1301 USA |
| 18 | */ |
| 19 | |
| 20 | |
| 21 | \f |
| 22 | #ifdef HAVE_CONFIG_H |
| 23 | # include <config.h> |
| 24 | #endif |
| 25 | |
| 26 | #include <errno.h> |
| 27 | #include <signal.h> /* for SIG constants */ |
| 28 | #include <stdlib.h> /* for getenv */ |
| 29 | #include <stdio.h> |
| 30 | |
| 31 | #include "libguile/_scm.h" |
| 32 | |
| 33 | #include "libguile/scmsigs.h" |
| 34 | #include "libguile/strings.h" |
| 35 | |
| 36 | #include "libguile/validate.h" |
| 37 | #include "libguile/simpos.h" |
| 38 | #include "libguile/dynwind.h" |
| 39 | |
| 40 | #ifdef HAVE_STRING_H |
| 41 | #include <string.h> |
| 42 | #endif |
| 43 | #include <unistd.h> |
| 44 | #if HAVE_SYS_WAIT_H |
| 45 | # include <sys/wait.h> |
| 46 | #endif |
| 47 | |
| 48 | #ifdef __MINGW32__ |
| 49 | # include <process.h> /* for spawnvp and friends */ |
| 50 | #endif |
| 51 | |
| 52 | #include "posix.h" |
| 53 | |
| 54 | \f |
| 55 | extern int system(); |
| 56 | \f |
| 57 | |
| 58 | #ifdef HAVE_SYSTEM |
| 59 | SCM_DEFINE (scm_system, "system", 0, 1, 0, |
| 60 | (SCM cmd), |
| 61 | "Execute @var{cmd} using the operating system's \"command\n" |
| 62 | "processor\". Under Unix this is usually the default shell\n" |
| 63 | "@code{sh}. The value returned is @var{cmd}'s exit status as\n" |
| 64 | "returned by @code{waitpid}, which can be interpreted using\n" |
| 65 | "@code{status:exit-val} and friends.\n" |
| 66 | "\n" |
| 67 | "If @code{system} is called without arguments, return a boolean\n" |
| 68 | "indicating whether the command processor is available.") |
| 69 | #define FUNC_NAME s_scm_system |
| 70 | { |
| 71 | int rv, eno; |
| 72 | char *c_cmd; |
| 73 | |
| 74 | if (SCM_UNBNDP (cmd)) |
| 75 | { |
| 76 | rv = system (NULL); |
| 77 | return scm_from_bool(rv); |
| 78 | } |
| 79 | SCM_VALIDATE_STRING (1, cmd); |
| 80 | errno = 0; |
| 81 | c_cmd = scm_to_locale_string (cmd); |
| 82 | rv = system (c_cmd); |
| 83 | eno = errno; free (c_cmd); errno = eno; |
| 84 | if (rv == -1 || (rv == 127 && errno != 0)) |
| 85 | SCM_SYSERROR; |
| 86 | return scm_from_int (rv); |
| 87 | } |
| 88 | #undef FUNC_NAME |
| 89 | #endif /* HAVE_SYSTEM */ |
| 90 | |
| 91 | |
| 92 | #ifdef HAVE_SYSTEM |
| 93 | |
| 94 | SCM_DEFINE (scm_system_star, "system*", 0, 0, 1, |
| 95 | (SCM args), |
| 96 | "Execute the command indicated by @var{args}. The first element must\n" |
| 97 | "be a string indicating the command to be executed, and the remaining\n" |
| 98 | "items must be strings representing each of the arguments to that\n" |
| 99 | "command.\n" |
| 100 | "\n" |
| 101 | "This function returns the exit status of the command as provided by\n" |
| 102 | "@code{waitpid}. This value can be handled with @code{status:exit-val}\n" |
| 103 | "and the related functions.\n" |
| 104 | "\n" |
| 105 | "@code{system*} is similar to @code{system}, but accepts only one\n" |
| 106 | "string per-argument, and performs no shell interpretation. The\n" |
| 107 | "command is executed using fork and execlp. Accordingly this function\n" |
| 108 | "may be safer than @code{system} in situations where shell\n" |
| 109 | "interpretation is not required.\n" |
| 110 | "\n" |
| 111 | "Example: (system* \"echo\" \"foo\" \"bar\")") |
| 112 | #define FUNC_NAME s_scm_system_star |
| 113 | { |
| 114 | if (scm_is_null (args)) |
| 115 | SCM_WRONG_NUM_ARGS (); |
| 116 | |
| 117 | if (scm_is_pair (args)) |
| 118 | { |
| 119 | SCM oldint; |
| 120 | SCM sig_ign; |
| 121 | SCM sigint; |
| 122 | /* SIGQUIT is undefined on MS-Windows. */ |
| 123 | #ifdef SIGQUIT |
| 124 | SCM oldquit; |
| 125 | SCM sigquit; |
| 126 | #endif |
| 127 | #ifdef HAVE_FORK |
| 128 | int pid; |
| 129 | #else |
| 130 | int status; |
| 131 | #endif |
| 132 | char **execargv; |
| 133 | |
| 134 | /* allocate before fork */ |
| 135 | execargv = scm_i_allocate_string_pointers (args); |
| 136 | |
| 137 | /* make sure the child can't kill us (as per normal system call) */ |
| 138 | sig_ign = scm_from_ulong ((unsigned long) SIG_IGN); |
| 139 | sigint = scm_from_int (SIGINT); |
| 140 | oldint = scm_sigaction (sigint, sig_ign, SCM_UNDEFINED); |
| 141 | #ifdef SIGQUIT |
| 142 | sigquit = scm_from_int (SIGQUIT); |
| 143 | oldquit = scm_sigaction (sigquit, sig_ign, SCM_UNDEFINED); |
| 144 | #endif |
| 145 | |
| 146 | #ifdef HAVE_FORK |
| 147 | pid = fork (); |
| 148 | if (pid == 0) |
| 149 | { |
| 150 | /* child */ |
| 151 | execvp (execargv[0], execargv); |
| 152 | |
| 153 | /* Something went wrong. */ |
| 154 | fprintf (stderr, "In execvp of %s: %s\n", |
| 155 | execargv[0], strerror (errno)); |
| 156 | |
| 157 | /* Exit directly instead of throwing, because otherwise this |
| 158 | process may keep on running. Use exit status 127, like |
| 159 | shells in this case, as per POSIX |
| 160 | <http://pubs.opengroup.org/onlinepubs/007904875/utilities/xcu_chap02.html#tag_02_09_01_01>. */ |
| 161 | _exit (127); |
| 162 | } |
| 163 | else |
| 164 | { |
| 165 | /* parent */ |
| 166 | int wait_result, status; |
| 167 | |
| 168 | if (pid == -1) |
| 169 | SCM_SYSERROR; |
| 170 | |
| 171 | SCM_SYSCALL (wait_result = waitpid (pid, &status, 0)); |
| 172 | if (wait_result == -1) |
| 173 | SCM_SYSERROR; |
| 174 | scm_sigaction (sigint, SCM_CAR (oldint), SCM_CDR (oldint)); |
| 175 | scm_sigaction (sigquit, SCM_CAR (oldquit), SCM_CDR (oldquit)); |
| 176 | |
| 177 | return scm_from_int (status); |
| 178 | } |
| 179 | #else /* !HAVE_FORK */ |
| 180 | status = spawnvp (P_WAIT, execargv[0], (const char * const *)execargv); |
| 181 | scm_sigaction (sigint, SCM_CAR (oldint), SCM_CDR (oldint)); |
| 182 | #ifdef SIGQUIT |
| 183 | scm_sigaction (sigquit, SCM_CAR (oldquit), SCM_CDR (oldquit)); |
| 184 | #endif |
| 185 | |
| 186 | return scm_from_int (status); |
| 187 | #endif /* !HAVE_FORK */ |
| 188 | } |
| 189 | else |
| 190 | SCM_WRONG_TYPE_ARG (1, args); |
| 191 | } |
| 192 | #undef FUNC_NAME |
| 193 | #endif /* HAVE_SYSTEM */ |
| 194 | |
| 195 | |
| 196 | SCM_DEFINE (scm_getenv, "getenv", 1, 0, 0, |
| 197 | (SCM nam), |
| 198 | "Looks up the string @var{nam} in the current environment. The return\n" |
| 199 | "value is @code{#f} unless a string of the form @code{NAME=VALUE} is\n" |
| 200 | "found, in which case the string @code{VALUE} is returned.") |
| 201 | #define FUNC_NAME s_scm_getenv |
| 202 | { |
| 203 | char *val; |
| 204 | char *var = scm_to_locale_string (nam); |
| 205 | val = getenv (var); |
| 206 | free (var); |
| 207 | return val ? scm_from_locale_string (val) : SCM_BOOL_F; |
| 208 | } |
| 209 | #undef FUNC_NAME |
| 210 | |
| 211 | /* Get an integer from an environment variable. */ |
| 212 | int |
| 213 | scm_getenv_int (const char *var, int def) |
| 214 | { |
| 215 | char *end = 0; |
| 216 | char *val = getenv (var); |
| 217 | long res = def; |
| 218 | if (!val) |
| 219 | return def; |
| 220 | res = strtol (val, &end, 10); |
| 221 | if (end == val) |
| 222 | return def; |
| 223 | return res; |
| 224 | } |
| 225 | |
| 226 | /* simple exit, without unwinding the scheme stack or flushing ports. */ |
| 227 | SCM_DEFINE (scm_primitive_exit, "primitive-exit", 0, 1, 0, |
| 228 | (SCM status), |
| 229 | "Terminate the current process without unwinding the Scheme\n" |
| 230 | "stack. The exit status is @var{status} if supplied, otherwise\n" |
| 231 | "zero.") |
| 232 | #define FUNC_NAME s_scm_primitive_exit |
| 233 | { |
| 234 | int cstatus = 0; |
| 235 | if (!SCM_UNBNDP (status)) |
| 236 | cstatus = scm_to_int (status); |
| 237 | exit (cstatus); |
| 238 | } |
| 239 | #undef FUNC_NAME |
| 240 | |
| 241 | SCM_DEFINE (scm_primitive__exit, "primitive-_exit", 0, 1, 0, |
| 242 | (SCM status), |
| 243 | "Terminate the current process using the _exit() system call and\n" |
| 244 | "without unwinding the Scheme stack. The exit status is\n" |
| 245 | "@var{status} if supplied, otherwise zero.\n" |
| 246 | "\n" |
| 247 | "This function is typically useful after a fork, to ensure no\n" |
| 248 | "Scheme cleanups or @code{atexit} handlers are run (those\n" |
| 249 | "usually belonging in the parent rather than the child).") |
| 250 | #define FUNC_NAME s_scm_primitive__exit |
| 251 | { |
| 252 | int cstatus = 0; |
| 253 | if (!SCM_UNBNDP (status)) |
| 254 | cstatus = scm_to_int (status); |
| 255 | _exit (cstatus); |
| 256 | } |
| 257 | #undef FUNC_NAME |
| 258 | |
| 259 | |
| 260 | |
| 261 | void |
| 262 | scm_init_simpos () |
| 263 | { |
| 264 | #include "libguile/simpos.x" |
| 265 | } |
| 266 | |
| 267 | |
| 268 | /* |
| 269 | Local Variables: |
| 270 | c-file-style: "gnu" |
| 271 | End: |
| 272 | */ |