1/* Utilities to execute a program in a subprocess (possibly linked by pipes
2   with other subprocesses), and wait for it.  Shared logic.
3   Copyright (C) 1996-2020 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#ifndef PEX_COMMON_H
22#define PEX_COMMON_H
23
24#include "config.h"
25#include "libiberty.h"
26#include <stdio.h>
27
28/* pid_t is may defined by config.h or sys/types.h needs to be
29   included.  */
30#if !defined(pid_t) && defined(HAVE_SYS_TYPES_H)
31#include <sys/types.h>
32#endif
33
34#define install_error_msg "installation problem, cannot exec `%s'"
35
36/* stdin file number.  */
37#define STDIN_FILE_NO 0
38
39/* stdout file number.  */
40#define STDOUT_FILE_NO 1
41
42/* stderr file number.  */
43#define STDERR_FILE_NO 2
44
45/* value of `pipe': port index for reading.  */
46#define READ_PORT 0
47
48/* value of `pipe': port index for writing.  */
49#define WRITE_PORT 1
50
51/* The structure used by pex_init and friends.  */
52
53struct pex_obj
54{
55  /* Flags.  */
56  int flags;
57  /* Name of calling program, for error messages.  */
58  const char *pname;
59  /* Base name to use for temporary files.  */
60  const char *tempbase;
61  /* Pipe to use as stdin for next process.  */
62  int next_input;
63  /* File name to use as stdin for next process.  */
64  char *next_input_name;
65  /* Whether next_input_name was allocated using malloc.  */
66  int next_input_name_allocated;
67  /* If not -1, stderr pipe from the last process.  */
68  int stderr_pipe;
69  /* Number of child processes.  */
70  int count;
71  /* PIDs of child processes; array allocated using malloc.  */
72  pid_t *children;
73  /* Exit statuses of child processes; array allocated using malloc.  */
74  int *status;
75  /* Time used by child processes; array allocated using malloc.  */
76  struct pex_time *time;
77  /* Number of children we have already waited for.  */
78  int number_waited;
79  /* FILE created by pex_input_file.  */
80  FILE *input_file;
81  /* FILE created by pex_read_output.  */
82  FILE *read_output;
83  /* FILE created by pex_read_err.  */
84  FILE *read_err;
85  /* Number of temporary files to remove.  */
86  int remove_count;
87  /* List of temporary files to remove; array allocated using malloc
88     of strings allocated using malloc.  */
89  char **remove;
90  /* Pointers to system dependent functions.  */
91  const struct pex_funcs *funcs;
92  /* For use by system dependent code.  */
93  void *sysdep;
94};
95
96/* Functions passed to pex_run_common.  */
97
98struct pex_funcs
99{
100  /* Open file NAME for reading.  If BINARY is non-zero, open in
101     binary mode.  Return >= 0 on success, -1 on error.  */
102  int (*open_read) (struct pex_obj *, const char */* name */, int /* binary */);
103  /* Open file NAME for writing.  If BINARY is non-zero, open in
104     binary mode.  Return >= 0 on success, -1 on error.  */
105  int (*open_write) (struct pex_obj *, const char */* name */,
106                     int /* binary */, int /* append */);
107  /* Execute a child process.  FLAGS, EXECUTABLE, ARGV, ERR are from
108     pex_run.  IN, OUT, ERRDES, TOCLOSE are all descriptors, from
109     open_read, open_write, or pipe, or they are one of STDIN_FILE_NO,
110     STDOUT_FILE_NO or STDERR_FILE_NO; if IN, OUT, and ERRDES are not
111     STD*_FILE_NO, they should be closed.  If the descriptor TOCLOSE
112     is not -1, and the system supports pipes, TOCLOSE should be
113     closed in the child process.  The function should handle the
114     PEX_STDERR_TO_STDOUT flag.  Return >= 0 on success, or -1 on
115     error and set *ERRMSG and *ERR.  */
116  pid_t (*exec_child) (struct pex_obj *, int /* flags */,
117                      const char */* executable */, char * const * /* argv */,
118                      char * const * /* env */,
119                      int /* in */, int /* out */, int /* errdes */,
120		      int /* toclose */, const char **/* errmsg */,
121		      int */* err */);
122  /* Close a descriptor.  Return 0 on success, -1 on error.  */
123  int (*close) (struct pex_obj *, int);
124  /* Wait for a child to complete, returning exit status in *STATUS
125     and time in *TIME (if it is not null).  CHILD is from fork.  DONE
126     is 1 if this is called via pex_free.  ERRMSG and ERR are as in
127     fork.  Return 0 on success, -1 on error.  */
128  pid_t (*wait) (struct pex_obj *, pid_t /* child */, int * /* status */,
129               struct pex_time * /* time */, int /* done */,
130               const char ** /* errmsg */, int * /* err */);
131  /* Create a pipe (only called if PEX_USE_PIPES is set) storing two
132     descriptors in P[0] and P[1].  If BINARY is non-zero, open in
133     binary mode.  Return 0 on success, -1 on error.  */
134  int (*pipe) (struct pex_obj *, int * /* p */, int /* binary */);
135  /* Get a FILE pointer to read from a file descriptor (only called if
136     PEX_USE_PIPES is set).  If BINARY is non-zero, open in binary
137     mode.  Return pointer on success, NULL on error.  */
138  FILE * (*fdopenr) (struct pex_obj *, int /* fd */, int /* binary */);
139  /* Get a FILE pointer to write to the file descriptor FD (only
140     called if PEX_USE_PIPES is set).  If BINARY is non-zero, open in
141     binary mode.  Arrange for FD not to be inherited by the child
142     processes.  Return pointer on success, NULL on error.  */
143  FILE * (*fdopenw) (struct pex_obj *, int /* fd */, int /* binary */);
144  /* Free any system dependent data associated with OBJ.  May be
145     NULL if there is nothing to do.  */
146  void (*cleanup) (struct pex_obj *);
147};
148
149extern struct pex_obj *pex_init_common (int, const char *, const char *,
150					const struct pex_funcs *);
151
152#endif
153