source: kBuild/vendor/gnumake/2005-05-16/commands.c

/* Command processing for GNU Make.
Copyright (C) 1988,89,91,92,93,94,95,96,97 Free Software Foundation, Inc.
This file is part of GNU Make.

GNU Make is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Make 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 General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Make; see the file COPYING.  If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

#include "make.h"
#include "dep.h"
#include "filedef.h"
#include "variable.h"
#include "job.h"
#include "commands.h"

#if VMS
# define FILE_LIST_SEPARATOR ','
#else
# define FILE_LIST_SEPARATOR ' '
#endif

extern int remote_kill PARAMS ((int id, int sig));

#ifndef HAVE_UNISTD_H
extern int getpid ();
#endif


/* Set FILE's automatic variables up.  */

void
set_file_variables (struct file *file)
{
  struct dep *d;
  char *at, *percent, *star, *less;

#ifndef NO_ARCHIVES
  /* If the target is an archive member `lib(member)',
     then $@ is `lib' and $% is `member'.  */

  if (ar_name (file->name))
    {
      unsigned int len;
      char *p;

      p = strchr (file->name, '(');
      at = (char *) alloca (p - file->name + 1);
      bcopy (file->name, at, p - file->name);
      at[p - file->name] = '\0';
      len = strlen (p + 1);
      percent = (char *) alloca (len);
      bcopy (p + 1, percent, len - 1);
      percent[len - 1] = '\0';
    }
  else
#endif  /* NO_ARCHIVES.  */
    {
      at = file->name;
      percent = "";
    }

  /* $* is the stem from an implicit or static pattern rule.  */
  if (file->stem == 0)
    {
      /* In Unix make, $* is set to the target name with
         any suffix in the .SUFFIXES list stripped off for
         explicit rules.  We store this in the `stem' member.  */
      register struct dep *d;
      char *name;
      unsigned int len;

#ifndef NO_ARCHIVES
      if (ar_name (file->name))
        {
          name = strchr (file->name, '(') + 1;
          len = strlen (name) - 1;
        }
      else
#endif
        {
          name = file->name;
          len = strlen (name);
        }

      for (d = enter_file (".SUFFIXES")->deps; d != 0; d = d->next)
        {
          unsigned int slen = strlen (dep_name (d));
          if (len > slen && strneq (dep_name (d), name + (len - slen), slen))
            {
              file->stem = savestring (name, len - slen);
              break;
            }
        }
      if (d == 0)
        file->stem = "";
    }
  star = file->stem;

  /* $< is the first not order-only dependency.  */
  less = "";
  for (d = file->deps; d != 0; d = d->next)
    if (!d->ignore_mtime)
      {
        less = dep_name (d);
        break;
      }

  if (file->cmds == default_file->cmds)
    /* This file got its commands from .DEFAULT.
       In this case $< is the same as $@.  */
    less = at;

#define DEFINE_VARIABLE(name, len, value) \
  (void) define_variable_for_file (name,len,value,o_automatic,0,file)

  /* Define the variables.  */

  DEFINE_VARIABLE ("<", 1, less);
  DEFINE_VARIABLE ("*", 1, star);
  DEFINE_VARIABLE ("@", 1, at);
  DEFINE_VARIABLE ("%", 1, percent);

  /* Compute the values for $^, $+, $?, and $|.  */

  {
    static char *plus_value=0, *bar_value=0, *qmark_value=0;
    static unsigned int qmark_max=0, plus_max=0, bar_max=0;

    unsigned int qmark_len, plus_len, bar_len;
    char *cp;
    char *caret_value;
    char *qp;
    char *bp;
    unsigned int len;

    /* Compute first the value for $+, which is supposed to contain
       duplicate dependencies as they were listed in the makefile.  */

    plus_len = 0;
    for (d = file->deps; d != 0; d = d->next)
      if (! d->ignore_mtime)
        plus_len += strlen (dep_name (d)) + 1;
    if (plus_len == 0)
      plus_len++;

    if (plus_len > plus_max)
      plus_value = (char *) xmalloc (plus_max = plus_len);
    cp = plus_value;

    qmark_len = plus_len + 1;   /* Will be this or less.  */
    for (d = file->deps; d != 0; d = d->next)
      if (! d->ignore_mtime)
        {
          char *c = dep_name (d);

#ifndef NO_ARCHIVES
          if (ar_name (c))
            {
              c = strchr (c, '(') + 1;
              len = strlen (c) - 1;
            }
          else
#endif
            len = strlen (c);

          bcopy (c, cp, len);
          cp += len;
          *cp++ = FILE_LIST_SEPARATOR;
          if (! d->changed)
            qmark_len -= len + 1;       /* Don't space in $? for this one.  */
        }

    /* Kill the last space and define the variable.  */

    cp[cp > plus_value ? -1 : 0] = '\0';
    DEFINE_VARIABLE ("+", 1, plus_value);

    /* Make sure that no dependencies are repeated.  This does not
       really matter for the purpose of updating targets, but it
       might make some names be listed twice for $^ and $?.  */

    uniquize_deps (file->deps);

    bar_len = 0;
    for (d = file->deps; d != 0; d = d->next)
      if (d->ignore_mtime)
        bar_len += strlen (dep_name (d)) + 1;
    if (bar_len == 0)
      bar_len++;

    /* Compute the values for $^, $?, and $|.  */

    cp = caret_value = plus_value; /* Reuse the buffer; it's big enough.  */

    if (qmark_len > qmark_max)
      qmark_value = (char *) xmalloc (qmark_max = qmark_len);
    qp = qmark_value;

    if (bar_len > bar_max)
      bar_value = (char *) xmalloc (bar_max = bar_len);
    bp = bar_value;

    for (d = file->deps; d != 0; d = d->next)
      {
        char *c = dep_name (d);

#ifndef NO_ARCHIVES
        if (ar_name (c))
          {
            c = strchr (c, '(') + 1;
            len = strlen (c) - 1;
          }
        else
#endif
          len = strlen (c);

        if (d->ignore_mtime)
          {
            bcopy (c, bp, len);
            bp += len;
            *bp++ = FILE_LIST_SEPARATOR;
          }
        else
          {
            bcopy (c, cp, len);
            cp += len;
            *cp++ = FILE_LIST_SEPARATOR;
            if (d->changed)
              {
                bcopy (c, qp, len);
                qp += len;
                *qp++ = FILE_LIST_SEPARATOR;
              }
          }
      }

    /* Kill the last spaces and define the variables.  */

    cp[cp > caret_value ? -1 : 0] = '\0';
    DEFINE_VARIABLE ("^", 1, caret_value);

    qp[qp > qmark_value ? -1 : 0] = '\0';
    DEFINE_VARIABLE ("?", 1, qmark_value);

    bp[bp > bar_value ? -1 : 0] = '\0';
    DEFINE_VARIABLE ("|", 1, bar_value);
  }

#undef  DEFINE_VARIABLE
}


/* Chop CMDS up into individual command lines if necessary.
   Also set the `lines_flags' and `any_recurse' members.  */

void
chop_commands (struct commands *cmds)
{
  register char *p;
  unsigned int nlines, idx;
  char **lines;

  /* If we don't have any commands,
     or we already parsed them, never mind.  */

  if (!cmds || cmds->command_lines != 0)
    return;

  /* Chop CMDS->commands up into lines in CMDS->command_lines.
         Also set the corresponding CMDS->lines_flags elements,
         and the CMDS->any_recurse flag.  */

  nlines = 5;
  lines = (char **) xmalloc (5 * sizeof (char *));
  idx = 0;
  p = cmds->commands;
  while (*p != '\0')
    {
      char *end = p;
    find_end:;
      end = strchr (end, '\n');
      if (end == 0)
        end = p + strlen (p);
      else if (end > p && end[-1] == '\\')
        {
          int backslash = 1;
          register char *b;
          for (b = end - 2; b >= p && *b == '\\'; --b)
            backslash = !backslash;
          if (backslash)
            {
              ++end;
              goto find_end;
            }
        }

      if (idx == nlines)
        {
          nlines += 2;
          lines = (char **) xrealloc ((char *) lines,
                                      nlines * sizeof (char *));
        }
      lines[idx++] = savestring (p, end - p);
      p = end;
      if (*p != '\0')
        ++p;
    }

  if (idx != nlines)
    {
      nlines = idx;
      lines = (char **) xrealloc ((char *) lines,
                                  nlines * sizeof (char *));
    }

  cmds->ncommand_lines = nlines;
  cmds->command_lines = lines;

  cmds->any_recurse = 0;
  cmds->lines_flags = (char *) xmalloc (nlines);
  for (idx = 0; idx < nlines; ++idx)
    {
      int flags = 0;

      for (p = lines[idx];
           isblank ((unsigned char)*p) || *p == '-' || *p == '@' || *p == '+';
           ++p)
        switch (*p)
          {
          case '+':
            flags |= COMMANDS_RECURSE;
            break;
          case '@':
            flags |= COMMANDS_SILENT;
            break;
          case '-':
            flags |= COMMANDS_NOERROR;
            break;
          }

      /* If no explicit '+' was given, look for MAKE variable references.  */
      if (!(flags & COMMANDS_RECURSE)
          && (strstr (p, "$(MAKE)") != 0 || strstr (p, "${MAKE}") != 0))
        flags |= COMMANDS_RECURSE;

      cmds->lines_flags[idx] = flags;
      cmds->any_recurse |= flags & COMMANDS_RECURSE;
    }
}


/* Execute the commands to remake FILE.  If they are currently executing,
   return or have already finished executing, just return.  Otherwise,
   fork off a child process to run the first command line in the sequence.  */

void
execute_file_commands (struct file *file)
{
  register char *p;

  /* Don't go through all the preparations if
     the commands are nothing but whitespace.  */

  for (p = file->cmds->commands; *p != '\0'; ++p)
    if (!isspace ((unsigned char)*p) && *p != '-' && *p != '@')
      break;
  if (*p == '\0')
    {
      /* If there are no commands, assume everything worked.  */
      set_command_state (file, cs_running);
      file->update_status = 0;
      notice_finished_file (file);
      return;
    }

  /* First set the automatic variables according to this file.  */

  initialize_file_variables (file, 0);

  set_file_variables (file);

  /* Start the commands running.  */
  new_job (file);
}


/* This is set while we are inside fatal_error_signal,
   so things can avoid nonreentrant operations.  */

int handling_fatal_signal = 0;

/* Handle fatal signals.  */

RETSIGTYPE
fatal_error_signal (int sig)
{
#ifdef __MSDOS__
  extern int dos_status, dos_command_running;

  if (dos_command_running)
    {
      /* That was the child who got the signal, not us.  */
      dos_status |= (sig << 8);
      return;
    }
  remove_intermediates (1);
  exit (EXIT_FAILURE);
#else /* not __MSDOS__ */
#ifdef _AMIGA
  remove_intermediates (1);
  if (sig == SIGINT)
     fputs (_("*** Break.\n"), stderr);

  exit (10);
#else /* not Amiga */
  handling_fatal_signal = 1;

  /* Set the handling for this signal to the default.
     It is blocked now while we run this handler.  */
  signal (sig, SIG_DFL);

  /* A termination signal won't be sent to the entire
     process group, but it means we want to kill the children.  */

  if (sig == SIGTERM)
    {
      register struct child *c;
      for (c = children; c != 0; c = c->next)
        if (!c->remote)
          (void) kill (c->pid, SIGTERM);
    }

  /* If we got a signal that means the user
     wanted to kill make, remove pending targets.  */

  if (sig == SIGTERM || sig == SIGINT
#ifdef SIGHUP
    || sig == SIGHUP
#endif
#ifdef SIGQUIT
    || sig == SIGQUIT
#endif
    )
    {
      register struct child *c;

      /* Remote children won't automatically get signals sent
         to the process group, so we must send them.  */
      for (c = children; c != 0; c = c->next)
        if (c->remote)
          (void) remote_kill (c->pid, sig);

      for (c = children; c != 0; c = c->next)
        delete_child_targets (c);

      /* Clean up the children.  We don't just use the call below because
         we don't want to print the "Waiting for children" message.  */
      while (job_slots_used > 0)
        reap_children (1, 0);
    }
  else
    /* Wait for our children to die.  */
    while (job_slots_used > 0)
      reap_children (1, 1);

  /* Delete any non-precious intermediate files that were made.  */

  remove_intermediates (1);

#ifdef SIGQUIT
  if (sig == SIGQUIT)
    /* We don't want to send ourselves SIGQUIT, because it will
       cause a core dump.  Just exit instead.  */
    exit (EXIT_FAILURE);
#endif

#ifdef WINDOWS32
  /* Cannot call W32_kill with a pid (it needs a handle) */
  exit (EXIT_FAILURE);
#else
  /* Signal the same code; this time it will really be fatal.  The signal
     will be unblocked when we return and arrive then to kill us.  */
  if (kill (getpid (), sig) < 0)
    pfatal_with_name ("kill");
#endif /* not WINDOWS32 */
#endif /* not Amiga */
#endif /* not __MSDOS__  */
}


/* Delete FILE unless it's precious or not actually a file (phony),
   and it has changed on disk since we last stat'd it.  */

static void
delete_target (struct file *file, char *on_behalf_of)
{
  struct stat st;
  int e;

  if (file->precious || file->phony)
    return;

#ifndef NO_ARCHIVES
  if (ar_name (file->name))
    {
      time_t file_date = (file->last_mtime == NONEXISTENT_MTIME
                          ? (time_t) -1
                          : (time_t) FILE_TIMESTAMP_S (file->last_mtime));
      if (ar_member_date (file->name) != file_date)
        {
          if (on_behalf_of)
            error (NILF, _("*** [%s] Archive member `%s' may be bogus; not deleted"),
                   on_behalf_of, file->name);
          else
            error (NILF, _("*** Archive member `%s' may be bogus; not deleted"),
                   file->name);
        }
      return;
    }
#endif

  EINTRLOOP (e, stat (file->name, &st));
  if (e == 0
      && S_ISREG (st.st_mode)
      && FILE_TIMESTAMP_STAT_MODTIME (file->name, st) != file->last_mtime)
    {
      if (on_behalf_of)
        error (NILF, _("*** [%s] Deleting file `%s'"), on_behalf_of, file->name);
      else
        error (NILF, _("*** Deleting file `%s'"), file->name);
      if (unlink (file->name) < 0
          && errno != ENOENT)   /* It disappeared; so what.  */
        perror_with_name ("unlink: ", file->name);
    }
}


/* Delete all non-precious targets of CHILD unless they were already deleted.
   Set the flag in CHILD to say they've been deleted.  */

void
delete_child_targets (struct child *child)
{
  struct dep *d;

  if (child->deleted)
    return;

  /* Delete the target file if it changed.  */
  delete_target (child->file, (char *) 0);

  /* Also remove any non-precious targets listed in the `also_make' member.  */
  for (d = child->file->also_make; d != 0; d = d->next)
    delete_target (d->file, child->file->name);

  child->deleted = 1;
}


/* Print out the commands in CMDS.  */

void
print_commands (struct commands *cmds)
{
  register char *s;

  fputs (_("#  commands to execute"), stdout);

  if (cmds->fileinfo.filenm == 0)
    puts (_(" (built-in):"));
  else
    printf (_(" (from `%s', line %lu):\n"),
            cmds->fileinfo.filenm, cmds->fileinfo.lineno);

  s = cmds->commands;
  while (*s != '\0')
    {
      char *end;

      while (isspace ((unsigned char)*s))
        ++s;

      end = strchr (s, '\n');
      if (end == 0)
        end = s + strlen (s);

      printf ("\t%.*s\n", (int) (end - s), s);

      s = end;
    }
}