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, 1997, 1998, 1999, 2000, 2001, 2003, 2004
4    Free Software Foundation, Inc.
5 
6 This file is part of the libiberty library.
7 Libiberty is free software; you can redistribute it and/or
8 modify it under the terms of the GNU Library General Public
9 License as published by the Free Software Foundation; either
10 version 2 of the License, or (at your option) any later version.
11 
12 Libiberty is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 Library General Public License for more details.
16 
17 You should have received a copy of the GNU Library General Public
18 License along with libiberty; see the file COPYING.LIB.  If not,
19 write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
20 Boston, MA 02110-1301, USA.  */
21 
22 #ifndef PEX_COMMON_H
23 #define PEX_COMMON_H
24 
25 #include "config.h"
26 #include "libiberty.h"
27 #include <stdio.h>
28 
29 /* pid_t is may defined by config.h or sys/types.h needs to be
30    included.  */
31 #if !defined(pid_t) && defined(HAVE_SYS_TYPES_H)
32 #include <sys/types.h>
33 #endif
34 
35 #define install_error_msg "installation problem, cannot exec `%s'"
36 
37 /* stdin file number.  */
38 #define STDIN_FILE_NO 0
39 
40 /* stdout file number.  */
41 #define STDOUT_FILE_NO 1
42 
43 /* stderr file number.  */
44 #define STDERR_FILE_NO 2
45 
46 /* value of `pipe': port index for reading.  */
47 #define READ_PORT 0
48 
49 /* value of `pipe': port index for writing.  */
50 #define WRITE_PORT 1
51 
52 /* The structure used by pex_init and friends.  */
53 
54 struct pex_obj
55 {
56   /* Flags.  */
57   int flags;
58   /* Name of calling program, for error messages.  */
59   const char *pname;
60   /* Base name to use for temporary files.  */
61   const char *tempbase;
62   /* Pipe to use as stdin for next process.  */
63   int next_input;
64   /* File name to use as stdin for next process.  */
65   char *next_input_name;
66   /* Whether next_input_name was allocated using malloc.  */
67   int next_input_name_allocated;
68   /* If not -1, stderr pipe from the last process.  */
69   int stderr_pipe;
70   /* Number of child processes.  */
71   int count;
72   /* PIDs of child processes; array allocated using malloc.  */
73   pid_t *children;
74   /* Exit statuses of child processes; array allocated using malloc.  */
75   int *status;
76   /* Time used by child processes; array allocated using malloc.  */
77   struct pex_time *time;
78   /* Number of children we have already waited for.  */
79   int number_waited;
80   /* FILE created by pex_input_file.  */
81   FILE *input_file;
82   /* FILE created by pex_read_output.  */
83   FILE *read_output;
84   /* FILE created by pex_read_err.  */
85   FILE *read_err;
86   /* Number of temporary files to remove.  */
87   int remove_count;
88   /* List of temporary files to remove; array allocated using malloc
89      of strings allocated using malloc.  */
90   char **remove;
91   /* Pointers to system dependent functions.  */
92   const struct pex_funcs *funcs;
93   /* For use by system dependent code.  */
94   void *sysdep;
95 };
96 
97 /* Functions passed to pex_run_common.  */
98 
99 struct pex_funcs
100 {
101   /* Open file NAME for reading.  If BINARY is non-zero, open in
102      binary mode.  Return >= 0 on success, -1 on error.  */
103   int (*open_read) (struct pex_obj *, const char */* name */, int /* binary */);
104   /* Open file NAME for writing.  If BINARY is non-zero, open in
105      binary mode.  Return >= 0 on success, -1 on error.  */
106   int (*open_write) (struct pex_obj *, const char */* name */,
107                      int /* binary */, int /* append */);
108   /* Execute a child process.  FLAGS, EXECUTABLE, ARGV, ERR are from
109      pex_run.  IN, OUT, ERRDES, TOCLOSE are all descriptors, from
110      open_read, open_write, or pipe, or they are one of STDIN_FILE_NO,
111      STDOUT_FILE_NO or STDERR_FILE_NO; if IN, OUT, and ERRDES are not
112      STD*_FILE_NO, they should be closed.  If the descriptor TOCLOSE
113      is not -1, and the system supports pipes, TOCLOSE should be
114      closed in the child process.  The function should handle the
115      PEX_STDERR_TO_STDOUT flag.  Return >= 0 on success, or -1 on
116      error and set *ERRMSG and *ERR.  */
117   pid_t (*exec_child) (struct pex_obj *, int /* flags */,
118                       const char */* executable */, char * const * /* argv */,
119                       char * const * /* env */,
120                       int /* in */, int /* out */, int /* errdes */,
121 		      int /* toclose */, const char **/* errmsg */,
122 		      int */* err */);
123   /* Close a descriptor.  Return 0 on success, -1 on error.  */
124   int (*close) (struct pex_obj *, int);
125   /* Wait for a child to complete, returning exit status in *STATUS
126      and time in *TIME (if it is not null).  CHILD is from fork.  DONE
127      is 1 if this is called via pex_free.  ERRMSG and ERR are as in
128      fork.  Return 0 on success, -1 on error.  */
129   pid_t (*wait) (struct pex_obj *, pid_t /* child */, int * /* status */,
130                struct pex_time * /* time */, int /* done */,
131                const char ** /* errmsg */, int * /* err */);
132   /* Create a pipe (only called if PEX_USE_PIPES is set) storing two
133      descriptors in P[0] and P[1].  If BINARY is non-zero, open in
134      binary mode.  Return 0 on success, -1 on error.  */
135   int (*pipe) (struct pex_obj *, int * /* p */, int /* binary */);
136   /* Get a FILE pointer to read from a file descriptor (only called if
137      PEX_USE_PIPES is set).  If BINARY is non-zero, open in binary
138      mode.  Return pointer on success, NULL on error.  */
139   FILE * (*fdopenr) (struct pex_obj *, int /* fd */, int /* binary */);
140   /* Get a FILE pointer to write to the file descriptor FD (only
141      called if PEX_USE_PIPES is set).  If BINARY is non-zero, open in
142      binary mode.  Arrange for FD not to be inherited by the child
143      processes.  Return pointer on success, NULL on error.  */
144   FILE * (*fdopenw) (struct pex_obj *, int /* fd */, int /* binary */);
145   /* Free any system dependent data associated with OBJ.  May be
146      NULL if there is nothing to do.  */
147   void (*cleanup) (struct pex_obj *);
148 };
149 
150 extern struct pex_obj *pex_init_common (int, const char *, const char *,
151 					const struct pex_funcs *);
152 
153 #endif
154