Commit | Line | Data |
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7e606af5 GE |
1 | /* |
2 | The software in this package is distributed under the GNU General | |
3 | Public License version 2 (with a special exception described below). | |
4 | ||
5 | A copy of GNU General Public License (GPL) is included in this distribution, | |
6 | in the file COPYING.GPL. | |
7 | ||
8 | As a special exception, if other files instantiate templates or use macros | |
9 | or inline functions from this file, or you compile this file and link it | |
10 | with other works to produce a work based on this file, this file | |
11 | does not by itself cause the resulting work to be covered | |
12 | by the GNU General Public License. | |
13 | ||
14 | However the source code for this file must still be made available | |
15 | in accordance with section (3) of the GNU General Public License. | |
16 | ||
17 | This exception does not invalidate any other reasons why a work based | |
18 | on this file might be covered by the GNU General Public License. | |
19 | */ | |
20 | /*************************************************************************** | |
21 | inpipestream.cpp - C++ streambuffer wrapper | |
22 | ------------------- | |
23 | begin : Thu Dec 27 2001 | |
24 | copyright : (C) 2001 by Intra2net AG | |
25 | ***************************************************************************/ | |
26 | ||
9e322fb7 | 27 | #include <errno.h> |
7e606af5 | 28 | #include <stdio.h> |
9e322fb7 | 29 | #include <string.h> |
ff5191e6 | 30 | #include <fcntl.h> |
f8f119bf | 31 | #include <sys/wait.h> |
9e322fb7 | 32 | #include <unistd.h> |
7e606af5 | 33 | |
7e606af5 GE |
34 | #include <streambuf> |
35 | #include <istream> | |
36 | #include <ostream> | |
37 | #include <cstdio> | |
9e322fb7 PG |
38 | #include <boost/foreach.hpp> |
39 | #include <boost/shared_array.hpp> | |
7e606af5 GE |
40 | |
41 | #include "exception.hxx" | |
9e322fb7 | 42 | #include "stringfunc.hxx" |
7e606af5 GE |
43 | #include "pipestream.hxx" |
44 | ||
f8f119bf GE |
45 | /** @brief runs command and returns it's output as string |
46 | * @param command the full command with all parameters | |
47 | * @param rescode struct containing the return code, if the program exited normally and so on | |
825c519f | 48 | * @param flags runtime control flags (stdio streams, environment, path lookup). |
f8f119bf GE |
49 | * @returns the output (stdout) of the called program |
50 | */ | |
9e322fb7 | 51 | template <typename CmdT> |
cc917897 | 52 | std::string capture_exec(CmdT command, ExecResult &rescode, |
825c519f | 53 | const int flags) |
f8f119bf GE |
54 | { |
55 | std::string output; | |
56 | ||
1d7539d5 | 57 | bool exit_set = false; |
f8f119bf GE |
58 | int exit_status_waitpid; |
59 | ||
60 | // set the results to false until we are sure we have proper values | |
61 | rescode.normal_exit = false; | |
62 | rescode.terminated_by_signal = false; | |
63 | ||
64 | try | |
65 | { | |
66 | { | |
825c519f | 67 | inpipestream ips(command, flags); |
f8f119bf GE |
68 | |
69 | ips.store_exit_status(&exit_set, &exit_status_waitpid); | |
70 | ||
71 | char buffer[2048]; | |
72 | while (ips.good()) | |
73 | { | |
74 | ips.read(buffer, sizeof(buffer)); | |
75 | output.append(buffer, ips.gcount()); | |
76 | } | |
77 | } | |
78 | ||
79 | // exit_status_waitpid only valid after destruction of the inpipestream | |
80 | ||
81 | if (exit_set) | |
82 | { | |
83 | rescode.normal_exit = WIFEXITED(exit_status_waitpid); | |
84 | if (rescode.normal_exit) | |
85 | rescode.return_code = WEXITSTATUS(exit_status_waitpid); | |
86 | ||
87 | rescode.terminated_by_signal = WIFSIGNALED(exit_status_waitpid); | |
88 | if (rescode.terminated_by_signal) | |
89 | rescode.signal = WTERMSIG(exit_status_waitpid); | |
90 | } | |
91 | } | |
92 | catch (pipestream_error &e) | |
93 | { | |
94 | rescode.error_message = e.what(); | |
95 | } | |
96 | ||
97 | return output; | |
98 | } | |
99 | ||
cc917897 PG |
100 | /** @brief Instantiation of \c capture_exec for STL string arguments. |
101 | * Caveat emptor: this will cause the backing stream to use \c | |
102 | * popen(3). To avoid shelling out, please refer to one of the | |
103 | * variants that allow passing an argument list. | |
104 | * | |
105 | * @param command String specifying the shell expression to be executed. | |
106 | * @param res (Out parameter) Store information about the termination | |
107 | * state in this struct. | |
108 | * | |
109 | * @returns Result of \c stdout. Note that due to the use of \c | |
110 | * popen, the correct way to collect stderr output as | |
111 | * well is to use shell redirection inside the expression | |
112 | * passed. | |
113 | */ | |
9e322fb7 | 114 | std::string capture_exec (const std::string &command, ExecResult &res) |
825c519f | 115 | { return capture_exec<const std::string &>(command, res, capture_flag::dflt); } |
cc917897 PG |
116 | |
117 | /** @brief Instantiation of \c capture_exec for argument lists. The | |
118 | * pipestream used to run the command will not shell out. | |
119 | * One of \c out or \c err must be set. | |
120 | * | |
121 | * @param command List of \c char* specifying the \c argv array of the | |
122 | * command to run. Note that the binary to executed is | |
123 | * assumed to be present at index 0 and that the input | |
124 | * is properly \c NULL terminated. | |
125 | * @param res (Out parameter) Store information about the termination | |
126 | * state in this struct. | |
825c519f PG |
127 | * @param flags Runtime control flags (stdio streams, environment, path |
128 | * lookup). | |
cc917897 PG |
129 | * |
130 | * @returns Captured output, combined into one string. | |
131 | */ | |
132 | std::string capture_exec (const char *const *command, ExecResult &res, | |
825c519f PG |
133 | const int flags) |
134 | { return capture_exec<const char *const *>(command, res, flags); } | |
cc917897 PG |
135 | |
136 | /** @brief Instantiation of \c capture_exec for argument lists. The | |
137 | * pipestream used to run the command will not shell out. | |
138 | * One of \c out or \c err must be set. | |
139 | * | |
140 | * @param command String vector specifying the \c argv array of the | |
141 | * command to run. Note that the binary to executed is | |
142 | * assumed to be present at index 0. | |
143 | * @param res (Out parameter) Store information about the termination | |
144 | * state in this struct. | |
825c519f PG |
145 | * @param flags Runtime control flags (stdio streams, environment, path |
146 | * lookup). | |
cc917897 PG |
147 | * |
148 | * @returns Captured output, combined into one string. | |
149 | */ | |
150 | std::string capture_exec (const std::vector<std::string> &command, ExecResult &res, | |
825c519f PG |
151 | const int flags) |
152 | { return capture_exec<const std::vector<std::string> &> (command, res, flags); } | |
c2c29997 | 153 | |
9e322fb7 PG |
154 | #define PIPE_CTOR_FAIL(where) \ |
155 | do { \ | |
156 | throw EXCEPTION (pipestream_error, \ | |
157 | std::string (where) + ": error " \ | |
158 | + I2n::to_string (errno) \ | |
159 | + " (" + std::string (strerror (errno)) + ")"); \ | |
160 | } while (0) | |
161 | ||
cc917897 PG |
162 | /** @brief Convert a string vector to a refcounted \c char** |
163 | * that is \c NULL terminated for use with e. g. \c execve(2). | |
164 | * | |
165 | * @param command List of arguments including the binary at index 0. | |
166 | * | |
167 | * @returns A \c boost::shared_array of pointers to the | |
168 | * arguments plus a trailing \c NULL. Note that | |
169 | * while the array itself is refcounted, the | |
170 | * pointees are assumed owned by the caller and | |
171 | * *not copyied*. I. e. they lose validity if the | |
172 | * original strings are freed. | |
173 | */ | |
9e322fb7 PG |
174 | static boost::shared_array <char *> |
175 | mk_argv (const std::vector<std::string> &command) | |
176 | { | |
177 | char **ret = NULL; | |
178 | ||
179 | try { | |
180 | ret = new char *[command.size () * sizeof (ret[0]) + 1]; | |
181 | } catch (std::bad_alloc &) { | |
182 | return boost::shared_array<char *> (); | |
183 | } | |
184 | ||
185 | size_t cur = 0; | |
186 | BOOST_FOREACH(const std::string &arg, command) { | |
187 | /* | |
188 | * Casting away constness is safe since the data is always | |
189 | * kept alive until after exec(). | |
190 | */ | |
191 | ret [cur++] = const_cast<char *> (arg.c_str ()); | |
192 | } | |
193 | ||
194 | ret [cur] = NULL; | |
195 | ||
196 | return boost::shared_array<char *> (ret); | |
197 | } | |
198 | ||
ff5191e6 PG |
199 | /** @brief Helper for redirecting a file descriptor to \c /dev/null. |
200 | * This will only acquire an fd the first time it is called | |
201 | * or if it is called after unsuccessfully attempting to | |
202 | * acquire one. | |
203 | * | |
204 | * @param fd The open file descriptor to operate on. | |
08199c66 | 205 | * @param save_errno Out parameter: stores errno here after a syscall failure. |
ff5191e6 PG |
206 | * |
207 | * @returns \c true on success, \c false otherwise (the call to | |
08199c66 PG |
208 | * either \c open(2) or \c dup2(2) failed), with errno |
209 | * communicated through saved_errno. | |
ff5191e6 PG |
210 | */ |
211 | static bool | |
08199c66 | 212 | redirect_devnull (const int fd, int &save_errno) |
ff5191e6 PG |
213 | { |
214 | static int nullfd = -1; | |
215 | ||
216 | errno = 0; | |
217 | if (nullfd == -1 && (nullfd = open ("/dev/null", O_RDWR)) == -1) { | |
08199c66 | 218 | save_errno = errno; |
ff5191e6 PG |
219 | return false; |
220 | } | |
221 | ||
222 | errno = 0; | |
223 | if (dup2 (nullfd, fd) == -1) { | |
08199c66 | 224 | save_errno = errno; |
ff5191e6 PG |
225 | return false; |
226 | } | |
227 | ||
228 | return true; | |
229 | } | |
230 | ||
cc917897 PG |
231 | /** @brief Helper aggregating common code for the shell-free ctors. |
232 | * | |
233 | * @param argv Argument list prepared for \c execve(2). | |
825c519f PG |
234 | * @param flags Control the runtime behavior wrt. stdio streams, \c |
235 | * *envp, and path search. One of \c collect_out or | |
236 | * \c collect_err is mandatory. All other flags are | |
237 | * optional. Pipebuf creation with fail with \c EINVAL | |
238 | * if that constraint is violated. | |
cc917897 PG |
239 | * |
240 | * @returns A \c FILE* handle for streaming if successful, \c NULL | |
241 | * otherwise. | |
825c519f PG |
242 | * |
243 | * Error handling strategy: | |
244 | * | |
245 | * - receive all errors from child as ints through a cloexec pipe; | |
246 | * - in the child, write error conditions always to pipe first, | |
247 | * then try to emit a more verbose log message; | |
248 | * - in the parent, throw on error indicating the child errno. | |
249 | * | |
250 | * Note that the error-pipe approach is robust due to guarantees by both | |
251 | * standard (POSIX) and implementation (Linux) of pipes: The read(2) from | |
252 | * the error channel will block until the pipe is either closed or written to; | |
253 | * hence no need to check for EAGAIN. Those writes are guaranteed to be atomic | |
254 | * because sizeof(errno) is less than PIPE_BUF; hence we can disregard EINTR. A | |
255 | * pipe whose write end (i.e. in the child) has been closed (by the kernel | |
256 | * because execve(2) was successful) will always indicate EOF by returning | |
257 | * zero, hence we know precisely whether everything went well or not. Cf. | |
258 | * pipe(7), sections “I/O on pipes and FIFOs” and “PIPE_BUF”, as well as | |
259 | * Kerrisk (2010), section 44.10, p. 917f. | |
cc917897 | 260 | */ |
17b459b3 | 261 | std::pair <pid_t, FILE *> |
cc917897 | 262 | inpipebuf::init_without_shell (const char *const *argv, |
825c519f | 263 | const int flags) const |
9e322fb7 PG |
264 | { |
265 | FILE *pipeobj = NULL; | |
08199c66 PG |
266 | int pipefd [2]; /* for reading output from the child */ |
267 | int errfd [2]; /* for determining a successful exec() */ | |
f2da42aa | 268 | sigset_t oldmask, newmask; |
825c519f | 269 | char *const *envp = flags & capture_flag::env_passthru ? environ : NULL; |
9e322fb7 | 270 | |
825c519f PG |
271 | if (!(flags & capture_flag::collect_any)) |
272 | { | |
cc917897 PG |
273 | errno = EINVAL; |
274 | PIPE_CTOR_FAIL("ctor"); | |
275 | } | |
276 | ||
825c519f PG |
277 | /* |
278 | * The error pipe must be openend with *O_CLOEXEC* set. We also open | |
279 | * the data pipe with close-on-exec and remove that bit only in the child. | |
280 | * The rationale is preventing the read fd from passed on if the parent | |
281 | * later re-forks another child: we intend it to be read from this (master) | |
282 | * process alone. | |
283 | */ | |
9e322fb7 | 284 | errno = 0; |
08199c66 PG |
285 | if ( ::pipe2 (pipefd, O_CLOEXEC) == -1 |
286 | || ::pipe2 (errfd , O_CLOEXEC) == -1) { | |
a30f9a22 | 287 | PIPE_CTOR_FAIL("pipe2"); |
9e322fb7 PG |
288 | } |
289 | ||
f2da42aa PG |
290 | sigfillset (&newmask); |
291 | sigprocmask (SIG_SETMASK, &newmask, &oldmask); | |
292 | ||
9e322fb7 PG |
293 | errno = 0; |
294 | pid_t childpid = fork (); | |
295 | switch (childpid) { | |
296 | case -1: { | |
f2da42aa | 297 | sigprocmask (SIG_SETMASK, &oldmask, NULL); |
9e322fb7 PG |
298 | PIPE_CTOR_FAIL("fork"); |
299 | break; | |
300 | } | |
301 | case 0: { | |
825c519f PG |
302 | /* |
303 | * Close read ends of error and data channels: the child is assumed | |
304 | * to write exclusively. | |
305 | */ | |
9e322fb7 | 306 | close (pipefd [0]); |
08199c66 | 307 | close (errfd [0]); |
9e322fb7 | 308 | |
825c519f PG |
309 | /* |
310 | * Remove cloexec bit from the write end of the pipe (this is the | |
311 | * only flag with F_SETFD). | |
312 | */ | |
a30f9a22 PG |
313 | fcntl (pipefd [1], F_SETFD, 0); |
314 | ||
08199c66 | 315 | int save_errno = 0; |
825c519f PG |
316 | |
317 | /* | |
318 | * Assign /dev/null if asked to close one of the streams, else | |
319 | * dup() it onto the pipe. | |
320 | */ | |
321 | if (!(flags & capture_flag::collect_out)) | |
322 | { | |
323 | if (!redirect_devnull (STDOUT_FILENO, save_errno)) | |
324 | { | |
08199c66 PG |
325 | (void)write (errfd [1], (char *)&save_errno, sizeof(save_errno)); |
326 | exit (EXIT_FAILURE); | |
ff5191e6 | 327 | } |
825c519f PG |
328 | } |
329 | else if (dup2 (pipefd[1], STDOUT_FILENO) == -1) | |
330 | { | |
08199c66 PG |
331 | (void)write (errfd [1], (char *)&save_errno, sizeof(save_errno)); |
332 | exit (EXIT_FAILURE); | |
9e322fb7 PG |
333 | } |
334 | ||
825c519f PG |
335 | if (!(flags & capture_flag::collect_err)) |
336 | { | |
337 | if (!redirect_devnull (STDERR_FILENO, save_errno)) | |
338 | { | |
08199c66 PG |
339 | (void)write (errfd [1], (char *)&save_errno, sizeof(save_errno)); |
340 | exit (EXIT_FAILURE); | |
ff5191e6 | 341 | } |
825c519f PG |
342 | } |
343 | else if (dup2 (pipefd[1], STDERR_FILENO) == -1) | |
344 | { | |
08199c66 PG |
345 | (void)write (errfd [1], (char *)&save_errno, sizeof(save_errno)); |
346 | exit (EXIT_FAILURE); | |
9e322fb7 PG |
347 | } |
348 | ||
825c519f PG |
349 | /* |
350 | * Close the write end of the pipe now that we have dup()’ed it | |
351 | * onto the stdio fds. The parent will now receive EOF on the pipe | |
352 | * when these fds are both closed. | |
353 | */ | |
17b459b3 PG |
354 | close (pipefd [1]); |
355 | ||
825c519f PG |
356 | /* |
357 | * Stop blocking signals so the child starts out with a sane | |
358 | * environment. | |
359 | */ | |
f2da42aa PG |
360 | sigprocmask (SIG_SETMASK, &oldmask, NULL); |
361 | ||
9e322fb7 | 362 | errno = 0; |
825c519f | 363 | if (flags & capture_flag::search_path) { |
cdc166d2 | 364 | execvpe (argv [0], const_cast <char *const *>(argv), envp); |
ad4490f1 | 365 | } else { |
cdc166d2 | 366 | execve (argv [0], const_cast <char *const *>(argv), envp); |
9e322fb7 | 367 | } |
08199c66 | 368 | |
825c519f PG |
369 | /* |
370 | * At this point, the call to execv[p]e() failed. Thus the error | |
371 | * pipe is still opened and we forward the errno through it. | |
372 | */ | |
08199c66 PG |
373 | (void)write (errfd [1], (char *)&errno, sizeof(errno)); |
374 | exit (EXIT_FAILURE); | |
9e322fb7 PG |
375 | break; |
376 | } | |
377 | default: { | |
9e322fb7 PG |
378 | break; |
379 | } | |
380 | } | |
381 | ||
825c519f PG |
382 | /* |
383 | * The parent is assumed to only consume data from either pipe, never | |
384 | * write. | |
385 | */ | |
08199c66 PG |
386 | close (pipefd [1]); |
387 | close (errfd [1]); | |
388 | ||
389 | /* | |
390 | * Check whether the child exec()’ed by reading from the error pipe. | |
391 | * The call to read(2) will block, uninterruptible due to signals being | |
392 | * blocked. If all went well, the read(2) will return zero bytes and we can | |
393 | * ditch the error channel. | |
394 | * | |
395 | * Otherwise either the read(2) failed or we actually received something | |
396 | * through the error pipe. Both cases are treated as errors and cause an | |
397 | * exit from the ctor. | |
398 | */ | |
399 | char buf [sizeof (errno)]; | |
400 | int ret; | |
401 | memset (buf, 0, sizeof (buf)); | |
402 | errno = 0; | |
403 | if ((ret = read (errfd [0], buf, sizeof (buf))) != 0) { | |
404 | close (pipefd [0]); | |
405 | close (errfd [0]); | |
406 | sigprocmask (SIG_SETMASK, &oldmask, NULL); | |
407 | if (ret == - 1) { | |
408 | /* read(2) failed */ | |
409 | PIPE_CTOR_FAIL("read"); | |
410 | } else { | |
411 | /* | |
412 | * We received data on the error channel indicating the child | |
413 | * process never successfully exec()’ed. We grab the error code | |
414 | * from the buffer and bail. | |
415 | */ | |
416 | errno = *((int *)&buf[0]); | |
417 | PIPE_CTOR_FAIL("child failed to exec()"); | |
418 | } | |
419 | } | |
420 | ||
421 | /* | |
422 | * read(2) yielded zero bytes; it’s safe to use the pipe so close our end | |
423 | * and continue. | |
424 | */ | |
425 | close (errfd [0]); | |
426 | ||
427 | sigprocmask (SIG_SETMASK, &oldmask, NULL); | |
428 | ||
429 | errno = 0; | |
430 | if ((pipeobj = fdopen (pipefd [0], "r")) == NULL) { | |
431 | close (pipefd [0]); | |
432 | PIPE_CTOR_FAIL("fdopen"); | |
433 | } | |
434 | ||
17b459b3 | 435 | return std::make_pair (childpid, pipeobj); |
9e322fb7 PG |
436 | } |
437 | ||
cc917897 | 438 | inpipebuf::inpipebuf(const char *const *command, |
825c519f | 439 | const int flags) |
9e322fb7 | 440 | : pipe (NULL) /* brr: shadowing global ident */ |
17b459b3 | 441 | , pid (-1) |
9e322fb7 PG |
442 | , status_set (NULL) |
443 | , exit_status (NULL) | |
444 | { | |
445 | if (command == NULL || command [0] == NULL) { | |
446 | PIPE_CTOR_FAIL("command"); | |
447 | } | |
448 | ||
825c519f | 449 | std::pair <pid_t, FILE *> tmp = this->init_without_shell (command, flags); |
17b459b3 PG |
450 | this->pid = tmp.first; /* no std::tie :/ */ |
451 | this->pipe = tmp.second; | |
9e322fb7 PG |
452 | |
453 | setg (&buffer, &buffer, &buffer); | |
454 | } | |
455 | ||
cc917897 | 456 | inpipebuf::inpipebuf(const std::vector<std::string> &command, |
825c519f | 457 | const int flags) |
c2c29997 | 458 | : pipe (NULL) /* brr: shadowing global ident */ |
17b459b3 | 459 | , pid (-1) |
c2c29997 PG |
460 | , status_set (NULL) |
461 | , exit_status (NULL) | |
462 | { | |
463 | if (command.empty ()) { | |
464 | PIPE_CTOR_FAIL("command"); | |
465 | } | |
466 | ||
467 | const boost::shared_array <char *> argv = mk_argv (command); | |
468 | if (!argv) { | |
469 | PIPE_CTOR_FAIL("malloc"); | |
470 | } | |
471 | ||
ad4490f1 | 472 | std::pair <pid_t, FILE *> tmp = |
825c519f | 473 | this->init_without_shell (argv.get (), flags); |
17b459b3 PG |
474 | this->pid = tmp.first; |
475 | this->pipe = tmp.second; | |
c2c29997 PG |
476 | |
477 | setg (&buffer, &buffer, &buffer); | |
478 | } | |
479 | ||
cc917897 | 480 | inpipebuf::inpipebuf(const std::string& command, |
825c519f | 481 | const int _ignored_flags) |
17b459b3 PG |
482 | : pid (-1) |
483 | , status_set (NULL) | |
484 | , exit_status (NULL) | |
7e606af5 | 485 | { |
7e606af5 GE |
486 | pipe = popen (command.c_str(), "r"); |
487 | if (pipe == NULL) | |
488 | throw EXCEPTION (pipestream_error, "can't open program or permission denied"); | |
489 | ||
490 | // force underflow | |
491 | setg (&buffer, &buffer, &buffer); | |
492 | } | |
493 | ||
494 | inpipebuf::~inpipebuf() | |
495 | { | |
496 | if (pipe != NULL) { | |
17b459b3 | 497 | int status; |
7e606af5 | 498 | |
17b459b3 | 499 | if (this->pid == -1) |
d00589a0 | 500 | { |
17b459b3 PG |
501 | errno = 0; |
502 | status = pclose (pipe); | |
503 | if (status != -1) { | |
504 | if (exit_status != NULL) { | |
505 | *exit_status = status; | |
506 | if (status_set != NULL) { | |
507 | *status_set = true; | |
508 | } | |
509 | } | |
510 | } | |
511 | } | |
512 | else | |
513 | { | |
514 | errno = 0; | |
515 | status = fclose (pipe); | |
516 | if (status != EOF) { | |
517 | if (exit_status != NULL) { | |
518 | *exit_status = status; /* might be overwritten below */ | |
519 | if (status_set != NULL) { | |
520 | *status_set = true; | |
521 | } | |
522 | } | |
523 | } | |
524 | ||
525 | errno = 0; | |
526 | while (waitpid (this->pid, &status, 0) == -1) { | |
527 | if (errno != EINTR) { | |
528 | status = -1; | |
529 | break; | |
530 | } | |
531 | } | |
532 | if (status != 0 && exit_status != NULL) { | |
533 | *exit_status = status; /* might overwrite pipe status above */ | |
534 | if (status_set != NULL) { | |
535 | *status_set = true; | |
536 | } | |
537 | } | |
7e606af5 GE |
538 | } |
539 | ||
540 | pipe = NULL; | |
541 | } | |
542 | } | |
543 | ||
544 | /** note: exit status only available after destruction */ | |
545 | void inpipebuf::store_exit_status(bool *_status_set, int *_exit_status) | |
546 | { | |
547 | status_set = _status_set; | |
548 | exit_status = _exit_status; | |
549 | } | |
550 | ||
551 | inpipebuf::int_type inpipebuf::underflow() | |
552 | { | |
553 | if (gptr() < egptr()) | |
554 | return traits_type::to_int_type(*gptr()); | |
555 | ||
556 | buffer = fgetc (pipe); | |
557 | if (feof (pipe)) | |
558 | { | |
559 | // ERROR or EOF | |
560 | return EOF; | |
561 | } | |
562 | ||
563 | setg (&buffer, &buffer, &buffer+sizeof(char)); | |
564 | ||
565 | return traits_type::to_int_type(*gptr()); | |
566 | } | |
567 | ||
7e606af5 GE |
568 | outpipebuf::outpipebuf(const std::string& command) |
569 | { | |
570 | status_set = NULL; | |
571 | exit_status = NULL; | |
572 | ||
573 | pipe = popen (command.c_str(), "w"); | |
574 | if (pipe == NULL) | |
575 | throw EXCEPTION (pipestream_error, "can't open program or permission denied"); | |
576 | } | |
577 | ||
578 | outpipebuf::~outpipebuf() | |
579 | { | |
580 | if (pipe != NULL) { | |
581 | int pclose_exit = pclose (pipe); | |
582 | ||
d00589a0 GE |
583 | if (exit_status && pclose_exit != -1) |
584 | { | |
585 | if (status_set) | |
586 | *status_set = true; | |
7e606af5 GE |
587 | *exit_status = pclose_exit; |
588 | } | |
589 | ||
590 | pipe = NULL; | |
591 | } | |
592 | } | |
593 | ||
594 | /** note: exit status only available after destruction */ | |
595 | void outpipebuf::store_exit_status(bool *_status_set, int *_exit_status) | |
596 | { | |
597 | status_set = _status_set; | |
598 | exit_status = _exit_status; | |
599 | } | |
600 | ||
601 | outpipebuf::int_type outpipebuf::overflow(int_type c) | |
602 | { | |
603 | if (c != EOF) | |
604 | { | |
605 | if (fputc(c,pipe)==EOF) | |
606 | return EOF; | |
607 | } | |
608 | return c; | |
609 | } | |
610 | ||
611 | std::streamsize outpipebuf::xsputn(const char* s, std::streamsize num) | |
612 | { | |
613 | return fwrite(s,num,1,pipe); | |
614 | } |