/* Copyright (C) 1995, 1996, 1998 Aladdin Enterprises.  All rights reserved.
  
  This file is part of GNU Ghostscript.
  
  GNU Ghostscript is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY.  No author or distributor accepts responsibility
  to anyone for the consequences of using it or for whether it serves any
  particular purpose or works at all, unless he says so in writing.  Refer
  to the GNU General Public License for full details.
  
  Everyone is granted permission to copy, modify and redistribute GNU
  Ghostscript, but only under the conditions described in the GNU General
  Public License.  A copy of this license is supposed to have been given
  to you along with GNU Ghostscript so you can know your rights and
  responsibilities.  It should be in a file named COPYING.  Among other
  things, the copyright notice and this notice must be preserved on all
  copies.
  
  Aladdin Enterprises supports the work of the GNU Project, but is not
  affiliated with the Free Software Foundation or the GNU Project.  GNU
  Ghostscript, as distributed by Aladdin Enterprises, does not require any
  GNU software to build or run it.
*/

/*$Id: geninit.c $ */
/* Utility for merging all the Ghostscript initialization files */
/* (gs_*.ps) into a single file, optionally converting them to C data. */
#include "stdpre.h"
#include <stdio.h>
#include <string.h>

/* Usage:
 *    geninit <init-file.ps> <gconfig.h> <merged-init-file.ps>
 *      geninit <init-file.ps> <gconfig.h> -c <merged-init-file.c>
 */

/* Forward references */
private void merge_to_c(P4(const char *inname, FILE * in, FILE * config,
			   FILE * out));
private void merge_to_ps(P4(const char *inname, FILE * in, FILE * config,
			    FILE * out));

#define LINE_SIZE 128

int
main(int argc, char *argv[])
{
    const char *fin;
    FILE *in;
    const char *fconfig;
    FILE *config;
    const char *fout;
    FILE *out;
    bool to_c = false;

    if (argc == 4)
	fin = argv[1], fconfig = argv[2], fout = argv[3];
    else if (argc == 5 && !strcmp(argv[3], "-c"))
	fin = argv[1], fconfig = argv[2], fout = argv[4], to_c = true;
    else {
	fprintf(stderr, "\
Usage: geninit gs_init.ps gconfig.h gs_xinit.ps\n\
or     geninit gs_init.ps gconfig.h -c gs_init.c\n");
	exit(1);
    }
    in = fopen(fin, "r");
    if (in == 0) {
	fprintf(stderr, "Cannot open %s for reading.\n", fin);
	exit(1);
    }
    config = fopen(fconfig, "r");
    if (config == 0) {
	fprintf(stderr, "Cannot open %s for reading.\n", fconfig);
	fclose(in);
	exit(1);
    }
    out = fopen(fout, "w");
    if (out == 0) {
	fprintf(stderr, "Cannot open %s for writing.\n", fout);
	fclose(config);
	fclose(in);
	exit(1);
    }
    if (to_c)
	merge_to_c(fin, in, config, out);
    else
	merge_to_ps(fin, in, config, out);
    fclose(out);
    return 0;
}

/* Read a line from the input. */
private bool
rl(FILE * in, char *str, int len)
{
    if (fgets(str, len, in) == NULL)
	return false;
    str[strlen(str) - 1] = 0;	/* remove newline */
    return true;
}

/* Write a line on the output. */
private void
wlc(FILE * out, const char *str)
{
    int n = 0;
    const char *p = str;

    for (; *p; ++p) {
	char c = *p;
	const char *format = "%d,";

	if (c >= 32 && c < 127)
	    format = (c == '\'' || c == '\\' ? "'\\%c'," : "'%c',");
	fprintf(out, format, c);
	if (++n == 15) {
	    fputs("\n", out);
	    n = 0;
	}
    }
    fputs("10,\n", out);
}
private void
wl(FILE * out, const char *str, bool to_c)
{
    if (to_c)
	wlc(out, str);
    else
	fprintf(out, "%s\n", str);
}

/*
 * Strip whitespace and comments from a line of PostScript code as possible.
 * Return a pointer to any string that remains, or NULL if none.
 * Note that this may store into the string.
 */
private char *
doit(char *line)
{
    char *str = line;
    char *from;
    char *to;
    int in_string = 0;

    while (*str == ' ' || *str == '\t')		/* strip leading whitespace */
	++str;
    if (*str == 0)		/* all whitespace */
	return NULL;
    if (!strncmp(str, "%END", 4))	/* keep these for .skipeof */
	return str;
    if (str[0] == '%')		/* comment line */
	return NULL;
    /*
     * Copy the string over itself removing:
     *  - All comments not within string literals;
     *  - Whitespace adjacent to []{};
     *  - Whitespace before /(;
     *  - Whitespace after ).
     */
    for (to = from = str; (*to = *from) != 0; ++from, ++to) {
	switch (*from) {
	    case '%':
		if (!in_string)
		    break;
		continue;
	    case ' ':
	    case '\t':
		if (to > str && !in_string && strchr(" \t[]{})", to[-1]))
		    --to;
		continue;
	    case '(':
		if (to > str && !in_string && strchr(" \t", to[-1]))
		    *--to = *from;
		++in_string;
		continue;
	    case ')':
		--in_string;
		continue;
	    case '/':
	    case '[':
	    case ']':
	    case '{':
	    case '}':
		if (to > str && !in_string && strchr(" \t", to[-1]))
		    *--to = *from;
		continue;
	    case '\\':
		if (from[1] == '\\' || from[1] == '(' || from[1] == ')')
		    *++to = *++from;
		continue;
	    default:
		continue;
	}
	break;
    }
    /* Strip trailing whitespace. */
    while (to > str && (to[-1] == ' ' || to[-1] == '\t'))
	--to;
    *to = 0;
    return str;
}

/* Merge a file from input to output. */
private void
flush_buf(FILE * out, char *buf, bool to_c)
{
    if (buf[0] != 0) {
	wl(out, buf, to_c);
	buf[0] = 0;
    }
}
private void
mergefile(const char *inname, FILE * in, FILE * config, FILE * out, bool to_c)
{
    char line[LINE_SIZE + 1];
    char buf[LINE_SIZE + 1];
    char *str;

    buf[0] = 0;
    while (rl(in, line, LINE_SIZE)) {
	char psname[LINE_SIZE + 1];
	int nlines;

	if (!strncmp(line, "%% Replace ", 11) &&
	    sscanf(line + 11, "%d %s", &nlines, psname) == 2
	    ) {
	    flush_buf(out, buf, to_c);
	    while (nlines-- > 0)
		rl(in, line, LINE_SIZE);
	    if (psname[0] == '(') {
		FILE *ps;

		psname[strlen(psname) - 1] = 0;
		ps = fopen(psname + 1, "r");
		if (ps == 0) {
		    fprintf(stderr, "Cannot open %s for reading.\n", psname + 1);
		    exit(1);
		}
		mergefile(psname + 1, ps, config, out, to_c);
	    } else if (!strcmp(psname, "INITFILES")) {
		/*
		 * We don't want to bind config.h into geninit, so
		 * we parse it ourselves at execution time instead.
		 */
		rewind(config);
		while (rl(config, psname, LINE_SIZE))
		    if (!strncmp(psname, "psfile_(\"", 9)) {
			FILE *ps;
			char *quote = strchr(psname + 9, '"');

			*quote = 0;
			ps = fopen(psname + 9, "r");
			if (ps == 0) {
			    fprintf(stderr, "Cannot open %s for reading.\n", psname + 9);
			    exit(1);
			}
			mergefile(psname + 9, ps, config, out, to_c);
		    }
	    } else {
		fprintf(stderr, "Unknown %%%% Replace %d %s\n",
			nlines, psname);
		exit(1);
	    }
	} else if (!strcmp(line, "currentfile closefile")) {
	    /* The rest of the file is debugging code, stop here. */
	    break;
	} else {
	    str = doit(line);
	    if (str == 0)
		continue;
	    if (buf[0] != '%' &&	/* special retained comment */
		strlen(buf) + strlen(str) < LINE_SIZE &&
		(strchr("(/[]{}", str[0]) ||
		 (buf[0] != 0 && strchr(")[]{}", buf[strlen(buf) - 1])))
		)
		strcat(buf, str);
	    else {
		flush_buf(out, buf, to_c);
		strcpy(buf, str);
	    }
	}
    }
    flush_buf(out, buf, to_c);
    fprintf(stderr, "%s: %ld bytes, output pos = %ld\n",
	    inname, ftell(in), ftell(out));
    fclose(in);
}

/* Merge and produce a C file. */
private void
merge_to_c(const char *inname, FILE * in, FILE * config, FILE * out)
{
    char line[LINE_SIZE + 1];

    fputs("/*\n", out);
    while ((rl(in, line, LINE_SIZE), line[0]))
	fprintf(out, "%s\n", line);
    fputs("*/\n", out);
    fputs("\n", out);
    fputs("/* Pre-compiled interpreter initialization string. */\n", out);
    fputs("\n", out);
    fputs("const unsigned char gs_init_string[] = {\n", out);
    mergefile(inname, in, config, out, true);
    fputs("10};\n", out);
    fputs("const unsigned int gs_init_string_sizeof = sizeof(gs_init_string);\n", out);
}

/* Merge and produce a PostScript file. */
private void
merge_to_ps(const char *inname, FILE * in, FILE * config, FILE * out)
{
    char line[LINE_SIZE + 1];

    while ((rl(in, line, LINE_SIZE), line[0]))
	fprintf(out, "%s\n", line);
    mergefile(inname, in, config, out, false);
}
