text: /* $OpenBSD: trace.c,v 1.6 2002/04/26 16:15:16 espie Exp $ */
  /*
   * Copyright (c) 2001 Marc Espie.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY THE OPENBSD PROJECT AND CONTRIBUTORS
   * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OPENBSD
   * PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   *
   * $FreeBSD: src/usr.bin/m4/trace.c,v 1.7 2002/07/15 02:15:12 jmallett Exp $
   * $DragonFly: src/usr.bin/m4/trace.c,v 1.3 2006/12/27 21:29:02 pavalos Exp $
   */
  
  #include <sys/types.h>
  #include <stddef.h>
  #include <stdio.h>
  #include <err.h>
  #include <stdlib.h>
  #include <string.h>
  #include "mdef.h"
  #include "stdd.h"
  #include "extern.h"
  
  FILE *traceout;
  
  int traced_macros = 0;
  
  #define TRACE_ARGS 	1
  #define TRACE_EXPANSION 2
  #define TRACE_QUOTE	4
  #define TRACE_FILENAME	8
  #define TRACE_LINENO	16
  #define TRACE_CONT	32
  #define TRACE_ID	64
  #define TRACE_NEWFILE	128	/* not implemented yet */
  #define TRACE_INPUT	256	/* not implemented yet */
  #define TRACE_ALL	512
  
  static struct t {
  	struct t *next;
  	char 	 *name;
  	int	  on;
  } *l;
  
  static unsigned int letter_to_flag(int);
  static void print_header(struct input_file *);
  static struct t *find_trace_entry(const char *);
  static int frame_level(void);
  
  static unsigned int flags = TRACE_QUOTE | TRACE_EXPANSION;
  
  static struct t *
  find_trace_entry(const char *name)
  {
  	struct t *n;
  
  	for (n = l; n != NULL; n = n->next)
  		if (STREQ(n->name, name))
  			return n;
  	return NULL;
  }
  
  
  void
  mark_traced(const char *name, int on)
  {
  	struct t *n, *n2;
  
  	traced_macros = 1;
  
  	if (name == NULL) {
  		if (on)
  			flags |= TRACE_ALL;
  		else {
  			flags &= ~TRACE_ALL;
  			traced_macros = 0;
  		}
  		for (n = l; n != NULL; n = n2) {
  			n2 = n->next;
  			free(n->name);
  			free(n);
  		}
  		l = NULL;
  	} else {
  	    n = find_trace_entry(name);
  	    if (n == NULL) {
  		    n = xalloc(sizeof(struct t));
  		    n->name = xstrdup(name);
  		    n->next = l;
  		    l = n;
  	    }
  	    n->on = on;
  	}
  }
  
  int
  is_traced(const char *name)
  {
  	struct t *n;
  
  	for (n = l; n != NULL; n = n->next)
  		if (STREQ(n->name, name))
  			return n->on;
  	return (flags & TRACE_ALL) ? 1 : 0;
  }
  
  void
  trace_file(const char *name)
  {
  
  	if (traceout != stderr)
  		fclose(traceout);
  	traceout = fopen(name, "w");
  	if (!traceout)
  		err(1, "can't open %s", name);
  }
  
  static unsigned int
  letter_to_flag(int c)
  {
  	switch(c) {
  	case 'a':
  		return TRACE_ARGS;
  	case 'e':
  		return TRACE_EXPANSION;
  	case 'q':
  		return TRACE_QUOTE;
  	case 'c':
  		return TRACE_CONT;
  	case 'x':
  		return TRACE_ID;
  	case 'f':
  		return TRACE_FILENAME;
  	case 'l':
  		return TRACE_LINENO;
  	case 'p':
  		return TRACE_NEWFILE;
  	case 'i':
  		return TRACE_INPUT;
  	case 't':
  		return TRACE_ALL;
  	case 'V':
  		return ~0;
  	default:
  		return 0;
  	}
  }
  
  void
  set_trace_flags(const char *s)
  {
  	char mode = 0;
  	unsigned int f = 0;
  
  	traced_macros = 1;
  
  	if (*s == '+' || *s == '-')
  		mode = *s++;
  	while (*s)
  		f |= letter_to_flag(*s++);
  	switch(mode) {
  	case 0:
  		flags = f;
  		break;
  	case '+':
  		flags |= f;
  		break;
  	case '-':
  		flags &= ~f;
  		break;
  	}
  }
  
  static int
  frame_level(void)
  {
  	int level;
  	int framep;
  
  	for (framep = fp, level = 0; framep != 0;
  		level++,framep = mstack[framep-2].sfra)
  		;
  	return level;
  }
  
  static void
  print_header(struct input_file *inp)
  {
  	fprintf(traceout, "m4trace:");
  	if (flags & TRACE_FILENAME)
  		fprintf(traceout, "%s:", inp->name);
  	if (flags & TRACE_LINENO)
  		fprintf(traceout, "%lu:", inp->lineno);
  	fprintf(traceout, " -%d- ", frame_level());
  	if (flags & TRACE_ID)
  		fprintf(traceout, "id %lu: ", expansion_id);
  }
  
  ssize_t
  trace(const char *argv[], int argc, struct input_file *inp)
  {
  	print_header(inp);
  	if (flags & TRACE_CONT) {
  		fprintf(traceout, "%s ...\n", argv[1]);
  		print_header(inp);
  	}
  	fprintf(traceout, "%s", argv[1]);
  	if ((flags & TRACE_ARGS) && argc > 2) {
  		char delim[3];
  		int i;
  
  		delim[0] = LPAREN;
  		delim[1] = EOS;
  		for (i = 2; i < argc; i++) {
  			fprintf(traceout, "%s%s%s%s", delim,
  			    (flags & TRACE_QUOTE) ? lquote : "",
  			    argv[i],
  			    (flags & TRACE_QUOTE) ? rquote : "");
  			delim[0] = COMMA;
  			delim[1] = ' ';
  			delim[2] = EOS;
  		}
  		fprintf(traceout, "%c", RPAREN);
  	}
  	if (flags & TRACE_CONT) {
  		fprintf(traceout, " -> ???\n");
  		print_header(inp);
  		fprintf(traceout, argc > 2 ? "%s(...)" : "%s", argv[1]);
  	}
  	if (flags & TRACE_EXPANSION)
  		return buffer_mark();
  	else {
  		fprintf(traceout, "\n");
  		return -1;
  	}
  }
  
  void
  finish_trace(size_t mark)
  {
  	fprintf(traceout, " -> ");
  	if (flags & TRACE_QUOTE)
  		fprintf(traceout, "%s", lquote);
  	dump_buffer(traceout, mark);
  	if (flags & TRACE_QUOTE)
  		fprintf(traceout, "%s", rquote);
  	fprintf(traceout, "\n");
  }
  