libiberty/pex-common.h

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