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Diffstat (limited to 'libiberty/pexecute.c')
| -rw-r--r-- | libiberty/pexecute.c | 580 |
1 files changed, 580 insertions, 0 deletions
diff --git a/libiberty/pexecute.c b/libiberty/pexecute.c new file mode 100644 index 00000000000..ab5f392780c --- /dev/null +++ b/libiberty/pexecute.c @@ -0,0 +1,580 @@ +/* Utilities to execute a program in a subprocess (possibly linked by pipes + with other subprocesses), and wait for it. + Copyright (C) 1996, 1997 Free Software Foundation, Inc. + +This file is part of the libiberty library. +Libiberty is free software; you can redistribute it and/or +modify it under the terms of the GNU Library General Public +License as published by the Free Software Foundation; either +version 2 of the License, or (at your option) any later version. + +Libiberty is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with libiberty; see the file COPYING.LIB. If not, +write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, +Boston, MA 02111-1307, USA. */ + +/* This file exports two functions: pexecute and pwait. */ + +/* This file lives in at least two places: libiberty and gcc. + Don't change one without the other. */ + +#include <stdio.h> +#include <errno.h> + +#ifdef IN_GCC +#include "config.h" +#include "gansidecl.h" +/* ??? Need to find a suitable header file. */ +#define PEXECUTE_FIRST 1 +#define PEXECUTE_LAST 2 +#define PEXECUTE_ONE (PEXECUTE_FIRST + PEXECUTE_LAST) +#define PEXECUTE_SEARCH 4 +#define PEXECUTE_VERBOSE 8 +#else +#include "libiberty.h" +#endif + +/* stdin file number. */ +#define STDIN_FILE_NO 0 + +/* stdout file number. */ +#define STDOUT_FILE_NO 1 + +/* value of `pipe': port index for reading. */ +#define READ_PORT 0 + +/* value of `pipe': port index for writing. */ +#define WRITE_PORT 1 + +static char *install_error_msg = "installation problem, cannot exec `%s'"; + +/* pexecute: execute a program. + + PROGRAM and ARGV are the arguments to execv/execvp. + + THIS_PNAME is name of the calling program (i.e. argv[0]). + + TEMP_BASE is the path name, sans suffix, of a temporary file to use + if needed. This is currently only needed for MSDOS ports that don't use + GO32 (do any still exist?). Ports that don't need it can pass NULL. + + (FLAGS & PEXECUTE_SEARCH) is non-zero if $PATH should be searched + (??? It's not clear that GCC passes this flag correctly). + (FLAGS & PEXECUTE_FIRST) is nonzero for the first process in chain. + (FLAGS & PEXECUTE_FIRST) is nonzero for the last process in chain. + FIRST_LAST could be simplified to only mark the last of a chain of processes + but that requires the caller to always mark the last one (and not give up + early if some error occurs). It's more robust to require the caller to + mark both ends of the chain. + + The result is the pid on systems like Unix where we fork/exec and on systems + like WIN32 and OS2 where we use spawn. It is up to the caller to wait for + the child. + + The result is the WEXITSTATUS on systems like MSDOS where we spawn and wait + for the child here. + + Upon failure, ERRMSG_FMT and ERRMSG_ARG are set to the text of the error + message with an optional argument (if not needed, ERRMSG_ARG is set to + NULL), and -1 is returned. `errno' is available to the caller to use. + + pwait: cover function for wait. + + PID is the process id of the task to wait for. + STATUS is the `status' argument to wait. + FLAGS is currently unused (allows future enhancement without breaking + upward compatibility). Pass 0 for now. + + The result is the pid of the child reaped, + or -1 for failure (errno says why). + + On systems that don't support waiting for a particular child, PID is + ignored. On systems like MSDOS that don't really multitask pwait + is just a mechanism to provide a consistent interface for the caller. + + pfinish: finish generation of script + + pfinish is necessary for systems like MPW where a script is generated that + runs the requested programs. +*/ + +#ifdef __MSDOS__ + +/* MSDOS doesn't multitask, but for the sake of a consistent interface + the code behaves like it does. pexecute runs the program, tucks the + exit code away, and returns a "pid". pwait must be called to fetch the + exit code. */ + +#include <process.h> + +/* For communicating information from pexecute to pwait. */ +static int last_pid = 0; +static int last_status = 0; +static int last_reaped = 0; + +int +pexecute (program, argv, this_pname, temp_base, errmsg_fmt, errmsg_arg, flags) + const char *program; + char * const *argv; + const char *this_pname; + const char *temp_base; + char **errmsg_fmt, **errmsg_arg; + int flags; +{ + int rc; + + last_pid++; + if (last_pid < 0) + last_pid = 1; + + if ((flags & PEXECUTE_ONE) != PEXECUTE_ONE) + abort (); + +#ifdef __GO32__ + /* ??? What are the possible return values from spawnv? */ + rc = (flags & PEXECUTE_SEARCH ? spawnvp : spawnv) (1, program, argv); +#else + char *scmd, *rf; + FILE *argfile; + int i, el = flags & PEXECUTE_SEARCH ? 4 : 0; + + scmd = (char *) xmalloc (strlen (program) + strlen (temp_base) + 6 + el); + rf = scmd + strlen(program) + 2 + el; + sprintf (scmd, "%s%s @%s.gp", program, + (flags & PEXECUTE_SEARCH ? ".exe" : ""), temp_base); + argfile = fopen (rf, "w"); + if (argfile == 0) + { + int errno_save = errno; + free (scmd); + errno = errno_save; + *errmsg_fmt = "cannot open `%s.gp'"; + *errmsg_arg = temp_base; + return -1; + } + + for (i=1; argv[i]; i++) + { + char *cp; + for (cp = argv[i]; *cp; cp++) + { + if (*cp == '"' || *cp == '\'' || *cp == '\\' || isspace (*cp)) + fputc ('\\', argfile); + fputc (*cp, argfile); + } + fputc ('\n', argfile); + } + fclose (argfile); + + rc = system (scmd); + + { + int errno_save = errno; + remove (rf); + free (scmd); + errno = errno_save; + } +#endif + + if (rc == -1) + { + *errmsg_fmt = install_error_msg; + *errmsg_arg = program; + return -1; + } + + /* Tuck the status away for pwait, and return a "pid". */ + last_status = rc << 8; + return last_pid; +} + +int +pwait (pid, status, flags) + int pid; + int *status; + int flags; +{ + /* On MSDOS each pexecute must be followed by it's associated pwait. */ + if (pid != last_pid + /* Called twice for the same child? */ + || pid == last_reaped) + { + /* ??? ECHILD would be a better choice. Can we use it here? */ + errno = EINVAL; + return -1; + } + /* ??? Here's an opportunity to canonicalize the values in STATUS. + Needed? */ + *status = last_status; + last_reaped = last_pid; + return last_pid; +} + +#endif /* MSDOS */ + +#if defined (_WIN32) + +#include <process.h> +extern int _spawnv (); +extern int _spawnvp (); + +int +pexecute (program, argv, this_pname, temp_base, errmsg_fmt, errmsg_arg, flags) + const char *program; + char * const *argv; + const char *this_pname; + const char *temp_base; + char **errmsg_fmt, **errmsg_arg; + int flags; +{ + int pid; + + if ((flags & PEXECUTE_ONE) != PEXECUTE_ONE) + abort (); + pid = (flags & PEXECUTE_SEARCH ? _spawnvp : _spawnv) (_P_NOWAIT, program, argv); + if (pid == -1) + { + *errmsg_fmt = install_error_msg; + *errmsg_arg = program; + return -1; + } + return pid; +} + +int +pwait (pid, status, flags) + int pid; + int *status; + int flags; +{ + /* ??? Here's an opportunity to canonicalize the values in STATUS. + Needed? */ + return cwait (status, pid, WAIT_CHILD); +} + +#endif /* _WIN32 */ + +#ifdef OS2 + +/* ??? Does OS2 have process.h? */ +extern int spawnv (); +extern int spawnvp (); + +int +pexecute (program, argv, this_pname, temp_base, errmsg_fmt, errmsg_arg, flags) + const char *program; + char * const *argv; + const char *this_pname; + const char *temp_base; + char **errmsg_fmt, **errmsg_arg; + int flags; +{ + int pid; + + if ((flags & PEXECUTE_ONE) != PEXECUTE_ONE) + abort (); + /* ??? Presumably 1 == _P_NOWAIT. */ + pid = (flags & PEXECUTE_SEARCH ? spawnvp : spawnv) (1, program, argv); + if (pid == -1) + { + *errmsg_fmt = install_error_msg; + *errmsg_arg = program; + return -1; + } + return pid; +} + +int +pwait (pid, status, flags) + int pid; + int *status; + int flags; +{ + /* ??? Here's an opportunity to canonicalize the values in STATUS. + Needed? */ + int pid = wait (status); + return pid; +} + +#endif /* OS2 */ + +#ifdef MPW + +/* MPW pexecute doesn't actually run anything; instead, it writes out + script commands that, when run, will do the actual executing. + + For example, in GCC's case, GCC will write out several script commands: + + cpp ... + cc1 ... + as ... + ld ... + + and then exit. None of the above programs will have run yet. The task + that called GCC will then execute the script and cause cpp,etc. to run. + The caller must invoke pfinish before calling exit. This adds + the finishing touches to the generated script. */ + +static int first_time = 1; + +int +pexecute (program, argv, this_pname, temp_base, errmsg_fmt, errmsg_arg, flags) + const char *program; + char **argv; + const char *this_pname; + const char *temp_base; + char **errmsg_fmt, **errmsg_arg; + int flags; +{ + char tmpprogram[255]; + char *cp, *tmpname; + int i; + + mpwify_filename (program, tmpprogram); + if (first_time) + { + printf ("Set Failed 0\n"); + first_time = 0; + } + + fputs ("If {Failed} == 0\n", stdout); + /* If being verbose, output a copy of the command. It should be + accurate enough and escaped enough to be "clickable". */ + if (flags & PEXECUTE_VERBOSE) + { + fputs ("\tEcho ", stdout); + fputc ('\'', stdout); + fputs (tmpprogram, stdout); + fputc ('\'', stdout); + fputc (' ', stdout); + for (i=1; argv[i]; i++) + { + /* We have to quote every arg, so that when the echo is + executed, the quotes are stripped and the original arg + is left. */ + fputc ('\'', stdout); + for (cp = argv[i]; *cp; cp++) + { + /* Write an Option-d esc char in front of special chars. */ + if (strchr ("\"'+", *cp)) + fputc ('\266', stdout); + fputc (*cp, stdout); + } + fputc ('\'', stdout); + fputc (' ', stdout); + } + fputs ("\n", stdout); + } + fputs ("\t", stdout); + fputs (tmpprogram, stdout); + fputc (' ', stdout); + + for (i=1; argv[i]; i++) + { + if (strchr (argv[i], ' ')) + fputc ('\'', stdout); + for (cp = argv[i]; *cp; cp++) + { + /* Write an Option-d esc char in front of special chars. */ + if (strchr ("\"'+", *cp)) + { + fputc ('\266', stdout); + } + fputc (*cp, stdout); + } + if (strchr (argv[i], ' ')) + fputc ('\'', stdout); + fputc (' ', stdout); + } + + fputs ("\n", stdout); + + /* Output commands that arrange to clean up and exit if a failure occurs. + We have to be careful to collect the status from the program that was + run, rather than some other script command. Also, we don't exit + immediately, since necessary cleanups are at the end of the script. */ + fputs ("\tSet TmpStatus {Status}\n", stdout); + fputs ("\tIf {TmpStatus} != 0\n", stdout); + fputs ("\t\tSet Failed {TmpStatus}\n", stdout); + fputs ("\tEnd\n", stdout); + fputs ("End\n", stdout); + + /* We're just composing a script, can't fail here. */ + return 0; +} + +int +pwait (pid, status, flags) + int pid; + int *status; + int flags; +{ + *status = 0; + return 0; +} + +/* Write out commands that will exit with the correct error code + if something in the script failed. */ + +void +pfinish () +{ + printf ("\tExit \"{Failed}\"\n"); +} + +#endif /* MPW */ + +/* include for Unix-like environments but not for Dos-like environments */ +#if ! defined (__MSDOS__) && ! defined (OS2) && ! defined (MPW) \ + && ! defined (_WIN32) + +#ifdef VMS +#define vfork() (decc$$alloc_vfork_blocks() >= 0 ? \ + lib$get_current_invo_context(decc$$get_vfork_jmpbuf()) : -1) +#else +#ifdef USG +#define vfork fork +#endif +#endif + +extern int execv (); +extern int execvp (); + +int +pexecute (program, argv, this_pname, temp_base, errmsg_fmt, errmsg_arg, flags) + const char *program; + char * const *argv; + const char *this_pname; + const char *temp_base; + char **errmsg_fmt, **errmsg_arg; + int flags; +{ + int (*func)() = (flags & PEXECUTE_SEARCH ? execvp : execv); + int pid; + int pdes[2]; + int input_desc, output_desc; + int retries, sleep_interval; + /* Pipe waiting from last process, to be used as input for the next one. + Value is STDIN_FILE_NO if no pipe is waiting + (i.e. the next command is the first of a group). */ + static int last_pipe_input; + + /* If this is the first process, initialize. */ + if (flags & PEXECUTE_FIRST) + last_pipe_input = STDIN_FILE_NO; + + input_desc = last_pipe_input; + + /* If this isn't the last process, make a pipe for its output, + and record it as waiting to be the input to the next process. */ + if (! (flags & PEXECUTE_LAST)) + { + if (pipe (pdes) < 0) + { + *errmsg_fmt = "pipe"; + *errmsg_arg = NULL; + return -1; + } + output_desc = pdes[WRITE_PORT]; + last_pipe_input = pdes[READ_PORT]; + } + else + { + /* Last process. */ + output_desc = STDOUT_FILE_NO; + last_pipe_input = STDIN_FILE_NO; + } + + /* Fork a subprocess; wait and retry if it fails. */ + sleep_interval = 1; + for (retries = 0; retries < 4; retries++) + { + pid = vfork (); + if (pid >= 0) + break; + sleep (sleep_interval); + sleep_interval *= 2; + } + + switch (pid) + { + case -1: + { +#ifdef vfork + *errmsg_fmt = "fork"; +#else + *errmsg_fmt = "vfork"; +#endif + *errmsg_arg = NULL; + return -1; + } + + case 0: /* child */ + /* Move the input and output pipes into place, if necessary. */ + if (input_desc != STDIN_FILE_NO) + { + close (STDIN_FILE_NO); + dup (input_desc); + close (input_desc); + } + if (output_desc != STDOUT_FILE_NO) + { + close (STDOUT_FILE_NO); + dup (output_desc); + close (output_desc); + } + + /* Close the parent's descs that aren't wanted here. */ + if (last_pipe_input != STDIN_FILE_NO) + close (last_pipe_input); + + /* Exec the program. */ + (*func) (program, argv); + + /* Note: Calling fprintf and exit here doesn't seem right for vfork. */ + fprintf (stderr, "%s: ", this_pname); + fprintf (stderr, install_error_msg, program); +#ifdef IN_GCC + fprintf (stderr, ": %s\n", my_strerror (errno)); +#else + fprintf (stderr, ": %s\n", xstrerror (errno)); +#endif + exit (-1); + /* NOTREACHED */ + return 0; + + default: + /* In the parent, after forking. + Close the descriptors that we made for this child. */ + if (input_desc != STDIN_FILE_NO) + close (input_desc); + if (output_desc != STDOUT_FILE_NO) + close (output_desc); + + /* Return child's process number. */ + return pid; + } +} + +int +pwait (pid, status, flags) + int pid; + int *status; + int flags; +{ + /* ??? Here's an opportunity to canonicalize the values in STATUS. + Needed? */ +#ifdef VMS + pid = waitpid (-1, status, 0); +#else + pid = wait (status); +#endif + return pid; +} + +#endif /* ! __MSDOS__ && ! OS2 && ! MPW && ! _WIN32 */ |