1/* Utilities to execute a program in a subprocess (possibly linked by pipes
2 with other subprocesses), and wait for it.
3 Copyright (C) 2004-2023 Free Software Foundation, Inc.
4
5This file is part of the libiberty library.
6Libiberty is free software; you can redistribute it and/or
7modify it under the terms of the GNU Library General Public
8License as published by the Free Software Foundation; either
9version 2 of the License, or (at your option) any later version.
10
11Libiberty is distributed in the hope that it will be useful,
12but WITHOUT ANY WARRANTY; without even the implied warranty of
13MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14Library General Public License for more details.
15
16You should have received a copy of the GNU Library General Public
17License along with libiberty; see the file COPYING.LIB. If not,
18write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
19Boston, MA 02110-1301, USA. */
20
21/* pexecute is an old routine. This implementation uses the newer
22 pex_init/pex_run/pex_get_status/pex_free routines. Don't use
23 pexecute in new code. Use the newer routines instead. */
24
25#include "config.h"
26#include "libiberty.h"
27
28#ifdef HAVE_STDLIB_H
29#include <stdlib.h>
30#endif
31
32/* We only permit a single pexecute chain to execute at a time. This
33 was always true anyhow, though it wasn't documented. */
34
35static struct pex_obj *pex;
36static int idx;
37
38int
39pexecute (const char *program, char * const *argv, const char *pname,
40 const char *temp_base, char **errmsg_fmt, char **errmsg_arg,
41 int flags)
42{
43 const char *errmsg;
44 int err;
45
46 if ((flags & PEXECUTE_FIRST) != 0)
47 {
48 if (pex != NULL)
49 {
50 *errmsg_fmt = (char *) "pexecute already in progress";
51 *errmsg_arg = NULL;
52 return -1;
53 }
54 pex = pex_init (PEX_USE_PIPES, pname, tempbase: temp_base);
55 idx = 0;
56 }
57 else
58 {
59 if (pex == NULL)
60 {
61 *errmsg_fmt = (char *) "pexecute not in progress";
62 *errmsg_arg = NULL;
63 return -1;
64 }
65 }
66
67 errmsg = pex_run (obj: pex,
68 flags: (((flags & PEXECUTE_LAST) != 0 ? PEX_LAST : 0)
69 | ((flags & PEXECUTE_SEARCH) != 0 ? PEX_SEARCH : 0)),
70 executable: program, argv, NULL, NULL, err: &err);
71 if (errmsg != NULL)
72 {
73 *errmsg_fmt = (char *) errmsg;
74 *errmsg_arg = NULL;
75 return -1;
76 }
77
78 /* Instead of a PID, we just return a one-based index into the
79 status values. We avoid zero just because the old pexecute would
80 never return it. */
81 return ++idx;
82}
83
84int
85pwait (int pid, int *status, int flags ATTRIBUTE_UNUSED)
86{
87 /* The PID returned by pexecute is one-based. */
88 --pid;
89
90 if (pex == NULL || pid < 0 || pid >= idx)
91 return -1;
92
93 if (pid == 0 && idx == 1)
94 {
95 if (!pex_get_status (pex, count: 1, vector: status))
96 return -1;
97 }
98 else
99 {
100 int *vector;
101
102 vector = XNEWVEC (int, idx);
103 if (!pex_get_status (pex, count: idx, vector))
104 {
105 free (ptr: vector);
106 return -1;
107 }
108 *status = vector[pid];
109 free (ptr: vector);
110 }
111
112 /* Assume that we are done after the caller has retrieved the last
113 exit status. The original implementation did not require that
114 the exit statuses be retrieved in order, but this implementation
115 does. */
116 if (pid + 1 == idx)
117 {
118 pex_free (pex);
119 pex = NULL;
120 idx = 0;
121 }
122
123 return pid + 1;
124}
125

source code of libiberty/pexecute.c