text: /* $Header$
   *
   * $Log$
   * Revision 1.1  2005/04/21 14:55:10  beng
   * Initial revision
   *
   * Revision 1.1.1.1  2005/04/20 13:33:18  beng
   * Initial import of minix 2.0.4
   *
   * Revision 2.0.1.1  88/06/03  15:06:13  lwall
   * patch10: made a little smarter about sccs files
   * 
   * Revision 2.0  86/09/17  15:37:02  lwall
   * Baseline for netwide release.
   * 
   */
  
  #include "EXTERN.h"
  #include "common.h"
  #include "util.h"
  #include "pch.h"
  #include "INTERN.h"
  #include "inp.h"
  
  /* Input-file-with-indexable-lines abstract type */
  
  static long i_size;			/* size of the input file */
  static char *i_womp;			/* plan a buffer for entire file */
  static char **i_ptr;			/* pointers to lines in i_womp */
  
  static int tifd = -1;			/* plan b virtual string array */
  static char *tibuf[2];			/* plan b buffers */
  static LINENUM tiline[2] = {-1, -1};	/* 1st line in each buffer */
  static LINENUM lines_per_buf;		/* how many lines per buffer */
  static int tireclen;			/* length of records in tmp file */
  
  /* New patch--prepare to edit another file. */
  
  void
  re_input()
  {
      if (using_plan_a) {
  	i_size = 0;
  #ifndef lint
  	if (i_ptr != Null(char**))
  	    free((char *)i_ptr);
  #endif
  	if (i_womp != Nullch)
  	    free(i_womp);
  	i_womp = Nullch;
  	i_ptr = Null(char **);
      }
      else {
  #ifndef SMALL
  	using_plan_a = TRUE;		/* maybe the next one is smaller */
  #endif
  	Close(tifd);
  	tifd = -1;
  	free(tibuf[0]);
  	free(tibuf[1]);
  	tibuf[0] = tibuf[1] = Nullch;
  	tiline[0] = tiline[1] = -1;
  	tireclen = 0;
      }
  }
  
  /* Constuct the line index, somehow or other. */
  
  void
  scan_input(filename)
  char *filename;
  {
  #ifndef SMALL
      if (!plan_a(filename))
  #endif
  	plan_b(filename);
      if (verbose) {
  	say3("Patching file %s using Plan %s...\n", filename,
  	  (using_plan_a ? "A" : "B") );
      }
  }
  
  #ifndef SMALL
  /* Try keeping everything in memory. */
  
  bool
  plan_a(filename)
  char *filename;
  {
      int ifd;
      Reg1 char *s;
      Reg2 LINENUM iline;
  
      if (ok_to_create_file && stat(filename, &filestat) < 0) {
  	if (verbose)
  	    say2("(Creating file %s...)\n",filename);
  	makedirs(filename, TRUE);
  	close(creat(filename, 0666));
      }
      if (stat(filename, &filestat) < 0) {
  	Sprintf(buf, "RCS/%s%s", filename, RCSSUFFIX);
  	if (stat(buf, &filestat) >= 0 || stat(buf+4, &filestat) >= 0) {
  	    Sprintf(buf, CHECKOUT, filename);
  	    if (verbose)
  		say2("Can't find %s--attempting to check it out from RCS.\n",
  		    filename);
  	    if (system(buf) || stat(filename, &filestat))
  		fatal2("Can't check out %s.\n", filename);
  	}
  	else {
  	    Sprintf(buf+20, "SCCS/%s%s", SCCSPREFIX, filename);
  	    if (stat(s=buf+20, &filestat) >= 0 ||
  	      stat(s=buf+25, &filestat) >= 0) {
  		Sprintf(buf, GET, s);
  		if (verbose)
  		    say2("Can't find %s--attempting to get it from SCCS.\n",
  			filename);
  		if (system(buf) || stat(filename, &filestat))
  		    fatal2("Can't get %s.\n", filename);
  	    }
  	    else
  		fatal2("Can't find %s.\n", filename);
  	}
      }
      filemode = filestat.st_mode;
      if ((filemode & S_IFMT) & ~S_IFREG)
  	fatal2("%s is not a normal file--can't patch.\n", filename);
      i_size = filestat.st_size;
      if (out_of_mem) {
  	set_hunkmax();		/* make sure dynamic arrays are allocated */
  	out_of_mem = FALSE;
  	return FALSE;			/* force plan b because plan a bombed */
      }
  #ifdef lint
      i_womp = Nullch;
  #else
      i_womp = malloc((MEM)(i_size+2));	/* lint says this may alloc less than */
  					/* i_size, but that's okay, I think. */
  #endif
      if (i_womp == Nullch)
  	return FALSE;
      if ((ifd = open(filename, 0)) < 0)
  	fatal2("Can't open file %s\n", filename);
  #ifndef lint
      if (read(ifd, i_womp, (int)i_size) != i_size) {
  	Close(ifd);	/* probably means i_size > 15 or 16 bits worth */
  	free(i_womp);	/* at this point it doesn't matter if i_womp was */
  	return FALSE;	/*   undersized. */
      }
  #endif
      Close(ifd);
      if (i_size && i_womp[i_size-1] != '\n')
  	i_womp[i_size++] = '\n';
      i_womp[i_size] = '\0';
  
      /* count the lines in the buffer so we know how many pointers we need */
  
      iline = 0;
      for (s=i_womp; *s; s++) {
  	if (*s == '\n')
  	    iline++;
      }
  #ifdef lint
      i_ptr = Null(char**);
  #else
      i_ptr = (char **)malloc((MEM)((iline + 2) * sizeof(char *)));
  #endif
      if (i_ptr == Null(char **)) {	/* shucks, it was a near thing */
  	free((char *)i_womp);
  	return FALSE;
      }
      
      /* now scan the buffer and build pointer array */
  
      iline = 1;
      i_ptr[iline] = i_womp;
      for (s=i_womp; *s; s++) {
  	if (*s == '\n')
  	    i_ptr[++iline] = s+1;	/* these are NOT null terminated */
      }
      input_lines = iline - 1;
  
      /* now check for revision, if any */
  
      if (revision != Nullch) { 
  	if (!rev_in_string(i_womp)) {
  	    if (force) {
  		if (verbose)
  		    say2(
  "Warning: this file doesn't appear to be the %s version--patching anyway.\n",
  			revision);
  	    }
  	    else {
  		ask2(
  "This file doesn't appear to be the %s version--patch anyway? [n] ",
  		    revision);
  	    if (*buf != 'y')
  		fatal1("Aborted.\n");
  	    }
  	}
  	else if (verbose)
  	    say2("Good.  This file appears to be the %s version.\n",
  		revision);
      }
      return TRUE;			/* plan a will work */
  }
  #endif
  
  /* Keep (virtually) nothing in memory. */
  
  void
  plan_b(filename)
  char *filename;
  {
      Reg3 FILE *ifp;
      Reg1 int i = 0;
      Reg2 int maxlen = 1;
      Reg4 bool found_revision = (revision == Nullch);
  
      using_plan_a = FALSE;
      if ((ifp = fopen(filename, "r")) == Nullfp)
  	fatal2("Can't open file %s\n", filename);
      if ((tifd = creat(TMPINNAME, 0666)) < 0)
  	fatal2("Can't open file %s\n", TMPINNAME);
      while (fgets(buf, sizeof buf, ifp) != Nullch) {
  	if (revision != Nullch && !found_revision && rev_in_string(buf))
  	    found_revision = TRUE;
  	if ((i = strlen(buf)) > maxlen)
  	    maxlen = i;			/* find longest line */
      }
      if (revision != Nullch) {
  	if (!found_revision) {
  	    if (force) {
  		if (verbose)
  		    say2(
  "Warning: this file doesn't appear to be the %s version--patching anyway.\n",
  			revision);
  	    }
  	    else {
  		ask2(
  "This file doesn't appear to be the %s version--patch anyway? [n] ",
  		    revision);
  		if (*buf != 'y')
  		    fatal1("Aborted.\n");
  	    }
  	}
  	else if (verbose)
  	    say2("Good.  This file appears to be the %s version.\n",
  		revision);
      }
      Fseek(ifp, 0L, 0);		/* rewind file */
      lines_per_buf = BUFFERSIZE / maxlen;
      tireclen = maxlen;
      tibuf[0] = (char *)malloc((MEM)(BUFFERSIZE + 1));
      tibuf[1] = (char *)malloc((MEM)(BUFFERSIZE + 1));
      if (tibuf[1] == Nullch)
  	fatal1("Can't seem to get enough memory.\n");
      for (i=1; ; i++) {
  	if (! (i % lines_per_buf))	/* new block */
  	    if (write(tifd, tibuf[0], BUFFERSIZE) < BUFFERSIZE)
  		fatal1("patch: can't write temp file.\n");
  	if (fgets(tibuf[0] + maxlen * (i%lines_per_buf), maxlen + 1, ifp)
  	  == Nullch) {
  	    input_lines = i - 1;
  	    if (i % lines_per_buf)
  		if (write(tifd, tibuf[0], BUFFERSIZE) < BUFFERSIZE)
  		    fatal1("patch: can't write temp file.\n");
  	    break;
  	}
      }
      Fclose(ifp);
      Close(tifd);
      if ((tifd = open(TMPINNAME, 0)) < 0) {
  	fatal2("Can't reopen file %s\n", TMPINNAME);
      }
  }
  
  /* Fetch a line from the input file, \n terminated, not necessarily \0. */
  
  char *
  ifetch(line,whichbuf)
  Reg1 LINENUM line;
  int whichbuf;				/* ignored when file in memory */
  {
      if (line < 1 || line > input_lines)
  	return "";
      if (using_plan_a)
  	return i_ptr[line];
      else {
  	LINENUM offline = line % lines_per_buf;
  	LINENUM baseline = line - offline;
  
  	if (tiline[0] == baseline)
  	    whichbuf = 0;
  	else if (tiline[1] == baseline)
  	    whichbuf = 1;
  	else {
  	    tiline[whichbuf] = baseline;
  #ifndef lint		/* complains of long accuracy */
  	    Lseek(tifd, (long)baseline / lines_per_buf * BUFFERSIZE, 0);
  #endif
  	    if (read(tifd, tibuf[whichbuf], BUFFERSIZE) < 0)
  		fatal2("Error reading tmp file %s.\n", TMPINNAME);
  	}
  	return tibuf[whichbuf] + (tireclen*offline);
      }
  }
  
  /* True if the string argument contains the revision number we want. */
  
  bool
  rev_in_string(string)
  char *string;
  {
      Reg1 char *s;
      Reg2 int patlen;
  
      if (revision == Nullch)
  	return TRUE;
      patlen = strlen(revision);
      if (strnEQ(string,revision,patlen) && isspace(s[patlen]))
  	return TRUE;
      for (s = string; *s; s++) {
  	if (isspace(*s) && strnEQ(s+1, revision, patlen) && 
  		isspace(s[patlen+1] )) {
  	    return TRUE;
  	}
      }
      return FALSE;
  }
  
  