mc/src/man2hlp.c

/* Man page to help file converter
   Copyright (C) 1994, 1995 Janne Kukonlehto
   
   This program 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 of the License, or
   (at your option) any later version.
   
   This program 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 this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>

#include "help.h"

#define BUFFER_SIZE 256

static int width;		/* Output width in characters */
static int col = 0;		/* Current output column */
static int out_row = 1;		/* Current output row */
static int in_row = 0;		/* Current input row */
static int no_split_flag = 0;	/* Flag: Don't split section on next ".SH" */
static int skip_flag = 0;	/* Flag: Skip this section.
				   0 = don't skip,
				   1 = skipping title,
				   2 = title skipped, skipping text */
static int link_flag = 0;	/* Flag: Next line is a link */
static int verbatim_flag = 0;	/* Flag: Copy input to output verbatim */
static int node = 0;		/* Flag: This line is an original ".SH" */

static const char *c_out;	/* Output filename */
static FILE *f_out;		/* Output file */

static char *Topics = "Topics:";

static struct node {
    char *node;
    char *lname;
    struct node *next;
} nodes, *cnode;

#define MAX_STREAM_BLOCK 8192

/*
 * Read in blocks of reasonable size and make sure we read everything.
 * Failure to read everything is an error.
 */
static size_t
persistent_fread (void *data, size_t len, FILE * stream)
{
    size_t count;
    size_t bytes_done = 0;
    char *ptr = (char *) data;

    while (bytes_done < len) {
	count = len - bytes_done;
	if (count > MAX_STREAM_BLOCK)
	    count = MAX_STREAM_BLOCK;

	count = fread (ptr, 1, count, stream);

	if (count <= 0)
	    return -1;

	bytes_done += count;
	ptr += count;
    }

    return bytes_done;
}

/*
 * Write in blocks of reasonable size and make sure we write everything.
 * Failure to write everything is an error.
 */
static size_t
persistent_fwrite (const void *data, size_t len, FILE * stream)
{
    size_t count;
    size_t bytes_done = 0;
    const char *ptr = (const char *) data;

    while (bytes_done < len) {
	count = len - bytes_done;
	if (count > MAX_STREAM_BLOCK)
	    count = MAX_STREAM_BLOCK;

	count = fwrite (ptr, 1, count, stream);

	if (count <= 0)
	    return -1;

	bytes_done += count;
	ptr += count;
    }

    return bytes_done;
}

/* Report error in input */
static void
print_error (char *message)
{
    fprintf (stderr, "man2hlp: %s in file \"%s\" at row %d\n", message,
	     c_out, in_row);
}

/* Change output line */
static void
newline (void)
{
    out_row++;
    col = 0;
    fprintf (f_out, "\n");
}

/* Calculate the length of string */
static int
string_len (char *buffer)
{
    static int anchor_flag = 0;	/* Flag: Inside hypertext anchor name */
    static int link_flag = 0;	/* Flag: Inside hypertext link target name */
    int backslash_flag = 0;	/* Flag: Backslash quoting */
    int c;			/* Current character */
    int len = 0;		/* Result: the length of the string */

    while (*(buffer)) {
	c = *buffer++;
	if (c == CHAR_LINK_POINTER)
	    link_flag = 1;	/* Link target name starts */
	else if (c == CHAR_LINK_END)
	    link_flag = 0;	/* Link target name ends */
	else if (c == CHAR_NODE_END) {
	    /* Node anchor name starts */
	    anchor_flag = 1;
	    /* Ugly hack to prevent loss of one space */
	    len++;
	}
	/* Don't add control characters to the length */
	if (c >= 0 && c < 32)
	    continue;
	/* Attempt to handle backslash quoting */
	if (c == '\\' && !backslash_flag) {
	    backslash_flag = 1;
	    continue;
	}
	backslash_flag = 0;
	/* Increase length if not inside anchor name or link target name */
	if (!anchor_flag && !link_flag)
	    len++;
	if (anchor_flag && c == ']') {
	    /* Node anchor name ends */
	    anchor_flag = 0;
	}
    }
    return len;
}

/* Output the string */
static void
print_string (char *buffer)
{
    int len;			/* The length of current word */
    int c;			/* Current character */
    int backslash_flag = 0;

    /* Skipping lines? */
    if (skip_flag)
	return;
    /* Copying verbatim? */
    if (verbatim_flag) {
	/* Attempt to handle backslash quoting */
	while (*(buffer)) {
	    c = *buffer++;
	    if (c == '\\' && !backslash_flag) {
		backslash_flag = 1;
		continue;
	    }
	    backslash_flag = 0;
	    fprintf (f_out, "%c", c);
	}
    } else {
	/* Split into words */
	buffer = strtok (buffer, " \t\n");
	/* Repeat for each word */
	while (buffer) {
	    /* Skip empty strings */
	    if (*(buffer)) {
		len = string_len (buffer);
		/* Change the line if about to break the right margin */
		if (col + len >= width)
		    newline ();
		/* Words are separated by spaces */
		if (col > 0) {
		    fprintf (f_out, " ");
		    col++;
		}
		/* Attempt to handle backslash quoting */
		while (*(buffer)) {
		    c = *buffer++;
		    if (c == '\\' && !backslash_flag) {
			backslash_flag = 1;
			continue;
		    }
		    backslash_flag = 0;
		    fprintf (f_out, "%c", c);
		}
		/* Increase column */
		col += len;
	    }
	    /* Get the next word */
	    buffer = strtok (NULL, " \t\n");
	}			/* while */
    }
}

/* Like print_string but with printf-like syntax */
static void
printf_string (char *format, ...)
{
    va_list args;
    char buffer[BUFFER_SIZE];

    va_start (args, format);
    vsprintf (buffer, format, args);
    va_end (args);
    print_string (buffer);
}

/* Handle all the roff dot commands */
static void
handle_command (char *buffer)
{
    int len, heading_level;

    /* Get the command name */
    strtok (buffer, " \t");
    if ((strcmp (buffer, ".SH") == 0)
	|| (strcmp (buffer, ".\\\"NODE") == 0)) {
	int SH = (strcmp (buffer, ".SH") == 0);
	/* If we already skipped a section, don't skip another */
	if (skip_flag == 2) {
	    skip_flag = 0;
	}
	/* Get the command parameters */
	buffer = strtok (NULL, "");
	if (buffer == NULL) {
	    print_error ("Syntax error: .SH: no title");
	    return;
	} else {
	    /* Remove quotes */
	    if (buffer[0] == '"') {
		buffer++;
		len = strlen (buffer);
		if (buffer[len - 1] == '"') {
		    len--;
		    buffer[len] = 0;
		}
	    }
	    /* Calculate heading level */
	    heading_level = 0;
	    while (buffer[heading_level] == ' ')
		heading_level++;
	    /* Heading level must be even */
	    if (heading_level & 1)
		print_error ("Syntax error: .SH: odd heading level");
	    if (no_split_flag) {
		/* Don't start a new section */
		newline ();
		print_string (buffer);
		newline ();
		newline ();
		no_split_flag = 0;
	    } else if (skip_flag) {
		/* Skipping title and marking text for skipping */
		skip_flag = 2;
	    } else {
		if (!SH || !node) {
		    /* Start a new section */
		    fprintf (f_out, "%c[%s]", CHAR_NODE_END,
			     buffer + heading_level);
		    if (!cnode) {
			cnode = &nodes;
			cnode->next = NULL;
		    } else {
			cnode->next = malloc (sizeof (nodes));
			cnode = cnode->next;
		    }
		    cnode->node = strdup (buffer);
		    cnode->lname = NULL;
		    col++;
		    newline ();
		}
		if (SH) {
		    /* print_string() strtok()es buffer, so */
		    cnode->lname = strdup (buffer + heading_level);
		    print_string (buffer + heading_level);
		    newline ();
		    newline ();
		}
	    }			/* Start new section */
	}			/* Has parameters */
	node = !SH;
    } /* Command .SH */
    else if (strcmp (buffer, ".\\\"DONT_SPLIT\"") == 0) {
	no_split_flag = 1;
    } else if (strcmp (buffer, ".\\\"SKIP_SECTION\"") == 0) {
	skip_flag = 1;
    } else if (strcmp (buffer, ".\\\"LINK2\"") == 0) {
	/* Next two input lines form a link */
	link_flag = 2;
    } else if (strcmp (buffer, ".PP") == 0) {
	/* End of paragraph */
	if (col > 0)
	    newline ();
	newline ();
    } else if (strcmp (buffer, ".nf") == 0) {
	/* Following input lines are to be handled verbatim */
	verbatim_flag = 1;
	if (col > 0)
	    newline ();
    } else if (strcmp (buffer, ".I") == 0 || strcmp (buffer, ".B") == 0) {
	/* Bold text or italics text */
	char type = buffer[1];
	char *p;
	char *w = buffer;
	int backslash_flag = 0;

	buffer = strtok (NULL, "");
	if (buffer == NULL) {
	    print_error ("Syntax error: .I / .B: no text");
	    return;
	}

	*w = (type == 'I') ? CHAR_ITALIC_ON : CHAR_BOLD_ON;

	/* Attempt to handle backslash quoting */
	for (p = buffer, buffer = w++; *p; p++) {
	    if (*p == '\\' && !backslash_flag) {
		backslash_flag = 1;
		continue;
	    }
	    backslash_flag = 0;
	    *w++ = *p;
	}

	*w++ = CHAR_BOLD_OFF;
	*w = 0;
	print_string (buffer);
    } else if (strcmp (buffer, ".TP") == 0) {
	/* End of paragraph? */
	if (col > 0)
	    newline ();
	newline ();
    } else if (strcmp (buffer, ".\\\"TOPICS") == 0) {
	if (out_row > 1) {
	    print_error
		("Syntax error: .\\\"TOPICS must be first command");
	    return;
	}
	buffer = strtok (NULL, "");
	if (buffer == NULL) {
	    print_error ("Syntax error: .\\\"TOPICS: no text");
	    return;
	}
	/* Remove quotes */
	if (buffer[0] == '"') {
	    buffer++;
	    len = strlen (buffer);
	    if (buffer[len - 1] == '"') {
		len--;
		buffer[len] = 0;
	    }
	}
	Topics = strdup (buffer);
    } else {
	/* Other commands are ignored */
    }
}

static void
handle_link (char *buffer)
{
    static char old[80];
    int len;

    switch (link_flag) {
    case 1:
	/* Old format link, not supported */
	break;
    case 2:
	/* First part of new format link */
	/* Bold text or italics text */
	if (buffer[0] == '.' && (buffer[1] == 'I' || buffer[1] == 'B'))
	    for (buffer += 2; *buffer == ' ' || *buffer == '\t'; buffer++);
	strcpy (old, buffer);
	link_flag = 3;
	break;
    case 3:
	/* Second part of new format link */
	if (buffer[0] == '.')
	    buffer++;
	if (buffer[0] == '\\')
	    buffer++;
	if (buffer[0] == '"')
	    buffer++;
	len = strlen (buffer);
	if (len && buffer[len - 1] == '"') {
	    buffer[--len] = 0;
	}
	printf_string ("%c%s%c%s%c\n", CHAR_LINK_START, old,
		       CHAR_LINK_POINTER, buffer, CHAR_LINK_END);
	link_flag = 0;
	break;
    }
}

int
main (int argc, char **argv)
{
    int len;			/* Length of input line */
    const char *c_man;		/* Manual filename */
    const char *c_tmpl;		/* Template filename */
    FILE *f_man;		/* Manual file */
    FILE *f_tmpl;		/* Template file */
    char buffer2[BUFFER_SIZE];	/* Temp input line */
    char *buffer = buffer2;	/* Input line */
    char *node = NULL;

    long cont_start, file_end;

    /* Validity check for arguments */
    if ((argc != 5) || ((width = atoi (argv[1])) <= 10)) {
	fprintf (stderr,
		 "Usage: man2hlp width file.man template_file helpfile\n");
	return 3;
    }

    c_man = argv[2];
    c_tmpl = argv[3];
    c_out = argv[4];

    /* Open the input file (manual) */
    f_man = fopen (c_man, "r");
    if (f_man == NULL) {
	sprintf (buffer, "man2hlp: Cannot open file \"%s\"", c_man);
	perror (buffer);
	return 3;
    }

    f_out = fopen (c_out, "w");
    if (f_out == NULL) {
	sprintf (buffer, "man2hlp: Cannot open file \"%s\"", c_out);
	perror (buffer);
	return 3;
    }

    /* Repeat for each input line */
    while (!feof (f_man)) {
	/* Read a line */
	if (!fgets (buffer2, BUFFER_SIZE, f_man)) {
	    break;
	}
	if (buffer2[0] == '\\' && buffer2[1] == '&')
	    buffer = buffer2 + 2;
	else
	    buffer = buffer2;
	in_row++;
	len = strlen (buffer);
	/* Remove terminating newline */
	if (buffer[len - 1] == '\n') {
	    len--;
	    buffer[len] = 0;
	}
	if (verbatim_flag) {
	    /* Copy the line verbatim */
	    if (strcmp (buffer, ".fi") == 0) {
		verbatim_flag = 0;
	    } else {
		print_string (buffer);
		newline ();
	    }
	} else if (link_flag)
	    /* The line is a link */
	    handle_link (buffer);
	else if (buffer[0] == '.')
	    /* The line is a roff command */
	    handle_command (buffer);
	else {
	    /* A normal line, just output it */
	    print_string (buffer);
	}
    }

    /* All done */
    newline ();
    fclose (f_man);

    /* Open the template file */
    f_tmpl = fopen (c_tmpl, "r");
    if (f_tmpl == NULL) {
	sprintf (buffer, "man2hlp: Cannot open file \"%s\"", c_tmpl);
	perror (buffer);
	return 3;
    }

    /* Repeat for each input line */
    while (!feof (f_tmpl)) {
	/* Read a line */
	if (!fgets (buffer2, BUFFER_SIZE, f_tmpl)) {
	    break;
	}
	if (node) {
	    if (*buffer2 && *buffer2 != '\n') {
		cnode->lname = strdup (buffer2);
		node = strchr (cnode->lname, '\n');
		if (node)
		    *node = 0;
	    }
	    node = NULL;
	} else {
	    node = strchr (buffer, CHAR_NODE_END);
	    if (node && (node[1] == '[')) {
		char *p = strrchr (node, ']');
		if (p && strncmp (node + 2, "main", 4) == 0
		    && node[6] == ']') {
		    node = 0;
		} else {
		    if (!cnode) {
			cnode = &nodes;
			cnode->next = NULL;
		    } else {
			cnode->next = malloc (sizeof (nodes));
			cnode = cnode->next;
		    }
		    cnode->node = strdup (node + 2);
		    cnode->node[p - node - 2] = 0;
		    cnode->lname = NULL;
		}
	    } else
		node = NULL;
	}
	fputs (buffer, f_out);
    }

    cont_start = ftell (f_out);
    fprintf (f_out, "\004[Contents]\n%s\n\n", Topics);

    for (cnode = &nodes; cnode && cnode->node;) {
	char *node = cnode->node;
	int heading_level = 0;
	struct node *next = cnode->next;

	while (*node == ' ') {
	    heading_level++;
	    node++;
	}
	if (*node)
	    fprintf (f_out, "  %*s\001 %s \002%s\003", heading_level, "",
		     cnode->lname ? cnode->lname : node, node);
	fprintf (f_out, "\n");

	free (cnode->node);
	if (cnode->lname)
	    free (cnode->lname);
	if (cnode != &nodes)
	    free (cnode);
	cnode = next;
    }

    file_end = ftell (f_out);
    fclose (f_out);

    if (file_end <= 0) {
	perror (c_out);
	return 1;
    }

    Topics = malloc (file_end);
    if (!Topics)
	return 1;

    f_out = fopen (c_out, "r");
    if (!f_out) {
	perror (c_out);
	return 1;
    }

    if (persistent_fread (Topics, file_end, f_out) < 0) {
	perror (c_out);
	return 1;
    }

    if (fclose (f_out) != 0) {
	perror (c_out);
	return 1;
    }

    f_out = fopen (c_out, "w");
    if (!f_out) {
	perror (c_out);
	return 1;
    }

    if (persistent_fwrite
	(Topics + cont_start, file_end - cont_start, f_out)
	< 0) {
	perror (c_out);
	return 1;
    }

    if (persistent_fwrite (Topics, cont_start, f_out) < 0) {
	perror (c_out);
	return 1;
    }

    free (Topics);

    if (fclose (f_out) != 0) {
	perror (c_out);
	return 1;
    }

    return 0;
}