lib/buildcmd.h

   1 /* buildcmd.[ch] -- build command lines from a stream of arguments
   2    Copyright (C) 2005, 2008 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16 */
  17 /*
  18  * Written by James Youngman.
  19  */
  20 #ifndef INC_BUILDCMD_H
  21 #define INC_BUILDCMD_H 1
  22
  23 struct buildcmd_state
  24 {
  25   /* Number of valid elements in `cmd_argv'.  */
  26   int cmd_argc;                 /* 0 */
  27
  28   /* The list of args being built.  */
  29   char **cmd_argv; /* NULL */
  30
  31   /* Number of elements allocated for `cmd_argv'.  */
  32   int cmd_argv_alloc;
  33
  34   /* Storage for elements of `cmd_argv'.  */
  35   char *argbuf;
  36
  37   /* Number of chars being used in `cmd_argv'.  */
  38   size_t cmd_argv_chars;
  39
  40   /* Number of chars being used in `cmd_argv' for the initial args..  */
  41   size_t cmd_initial_argv_chars;
  42
  43   /* User context information. */
  44   void *usercontext;
  45
  46   /* to-do flag. */
  47   int todo;
  48
  49   /* Directory in which to perform the exec. */
  50   int dir_fd;
  51 };
  52
  53 struct buildcmd_control
  54 {
  55   /* If true, exit if lines_per_exec or args_per_exec is exceeded.  */
  56   int exit_if_size_exceeded; /* false */
  57
  58   /* POSIX limits on the argument length. */
  59   size_t posix_arg_size_max;
  60   size_t posix_arg_size_min;
  61
  62   /* The maximum number of characters that can be used per command line.  */
  63   size_t arg_max;
  64
  65   /* max_arg_count: the maximum number of arguments that can be used.
  66    *
  67    * Many systems include the size of the pointers in ARG_MAX.
  68    * Linux on PPC fails if we just subtract 1 here.
  69    *
  70    * However, not all systems define ARG_MAX.  Our bc_get_arg_max()
  71    * function returns a useful value even if ARG_MAX is not defined.
  72    * However, sometimes, max_arg_count is LONG_MAX!
  73    */
  74   long max_arg_count;
  75
  76
  77   /* The length of `replace_pat'.  */
  78   size_t rplen;
  79
  80   /* If nonzero, then instead of putting the args from stdin at
  81    the end of the command argument list, they are each stuck into the
  82    initial args, replacing each occurrence of the `replace_pat' in the
  83    initial args.  */
  84   char *replace_pat;
  85
  86   /* Number of initial arguments given on the command line.  */
  87   int initial_argc;             /* 0 */
  88
  89   /* exec callback. */
  90   int (*exec_callback)(const struct buildcmd_control *, struct buildcmd_state *);
  91
  92   /* If nonzero, the maximum number of nonblank lines from stdin to use
  93      per command line.  */
  94   long lines_per_exec;          /* 0 */
  95
  96   /* The maximum number of arguments to use per command line.  */
  97   long args_per_exec;
  98 };
  99
 100 enum BC_INIT_STATUS
 101   {
 102     BC_INIT_OK = 0,
 103     BC_INIT_ENV_TOO_BIG,
 104     BC_INIT_CANNOT_ACCOMODATE_HEADROOM
 105   };
 106
 107 extern size_t bc_size_of_environment (void);
 108
 109
 110 extern void bc_do_insert (const struct buildcmd_control *ctl,
 111                           struct buildcmd_state *state,
 112                           char *arg, size_t arglen,
 113                           const char *prefix, size_t pfxlen,
 114                           const char *linebuf, size_t lblen,
 115                           int initial_args);
 116
 117 extern void bc_push_arg (const struct buildcmd_control *ctl,
 118                          struct buildcmd_state *state,
 119                          const char *arg,    size_t len,
 120                          const char *prefix, size_t pfxlen,
 121                          int initial_args);
 122
 123 extern void  bc_init_state(const struct buildcmd_control *ctl,
 124                            struct buildcmd_state *state,
 125                            void *usercontext);
 126 extern enum BC_INIT_STATUS bc_init_controlinfo(struct buildcmd_control *ctl,
 127                                                size_t arglen_headroom);
 128 extern size_t bc_get_arg_max(void);
 129 extern void bc_use_sensible_arg_max(struct buildcmd_control *ctl);
 130 extern void bc_clear_args(const struct buildcmd_control *ctl,
 131                           struct buildcmd_state *state);
 132
 133
 134 #endif