edit.c

具有IDE功能的编辑器

/* editor low level data handling and cursor fundamentals.

   Copyright (C) 1996-2000 the Free Software Foundation
   
   Authors: 1996, 1997 Paul Sheer

   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.
*/

#define _EDIT_C THIS_IS

#include <config.h>
#if defined(NEEDS_IO_H)
#    include <io.h>
#    include <fcntl.h>
#    define CR_LF_TRANSLATION
#endif
#include "edit.h"

#ifdef SCO_FLAVOR
#	include <sys/timeb.h>
#endif /* SCO_FLAVOR */
#include <time.h>	/* for ctime() */
#if defined (HAVE_MAD) && ! defined (MIDNIGHT) && ! defined (GTK)
#include "mad.h"
#endif

/*
 *
 * here's a quick sketch of the layout: (don't run this through indent.)
 * 
 * (b1 is buffers1 and b2 is buffers2)
 * 
 *                                       |
 * \0\0\0\0\0m e _ f i l e . \nf i n . \n|T h i s _ i s _ s o\0\0\0\0\0\0\0\0\0
 * ______________________________________|______________________________________
 *                                       |
 * ...  |  b2[2]   |  b2[1]   |  b2[0]   |  b1[0]   |  b1[1]   |  b1[2]   | ...
 *      |->        |->        |->        |->        |->        |->        |
 *                                       |
 *           _<------------------------->|<----------------->_
 *                   WEdit->curs2        |   WEdit->curs1
 *           ^                           |                   ^
 *           |                          ^|^                  |
 *         cursor                       |||                cursor
 *                                      |||
 *                              file end|||file beginning
 *                                       |
 *                                       |
 * 
 *           _
 * This_is_some_file
 * fin.
 *
 *
 */

/*
   returns a byte from any location in the file.
   Returns '\n' if out of bounds.
 */

static int push_action_disabled = 0;

#ifdef NO_INLINE_GETBYTE

int edit_get_byte (WEdit * edit, long byte_index)
{
    unsigned long p;
    if (byte_index >= (edit->curs1 + edit->curs2) || byte_index < 0)
	return '\n';

    if (byte_index >= edit->curs1) {
	p = edit->curs1 + edit->curs2 - byte_index - 1;
	return edit->buffers2[p >> S_EDIT_BUF_SIZE][EDIT_BUF_SIZE - (p & M_EDIT_BUF_SIZE) - 1];
    } else {
	return edit->buffers1[byte_index >> S_EDIT_BUF_SIZE][byte_index & M_EDIT_BUF_SIZE];
    }
}

#endif

char *edit_get_buffer_as_text (WEdit * e)
{
    int l, i;
    char *t;
    l = e->curs1 + e->curs2;
    t = CMalloc (l + 1);
    for (i = 0; i < l; i++)
	t[i] = edit_get_byte (e, i);
    t[l] = 0;
    return t;
}


/* Note on CRLF->LF translation: */

#if MY_O_TEXT
#error MY_O_TEXT is depreciated. CR_LF_TRANSLATION must be defined which does CR-LF translation internally. See note in source.
#endif

/* 
   The edit_open_file (previously edit_load_file) function uses
   init_dynamic_edit_buffers to load a file. This is unnecessary
   since you can just as well fopen the file and insert the
   characters one by one. The real reason for
   init_dynamic_edit_buffers (besides allocating the buffers) is
   as an optimisation - it uses raw block reads and inserts large
   chunks at a time. It is hence extremely fast at loading files.
   Where we might not want to use it is if we were doing
   CRLF->LF translation or if we were reading from a pipe.
 */

/* Initialisation routines */

/* returns 1 on error */
/* loads file OR text into buffers. Only one must be none-NULL. */
/* cursor set to start of file */
/* FIXME: implement proper error handling on failed reads */
int init_dynamic_edit_buffers (WEdit * edit, const char *filename, const char *text)
{
    long buf;
    int j, file = -1, buf2;

    for (j = 0; j <= MAXBUFF; j++) {
	edit->buffers1[j] = NULL;
	edit->buffers2[j] = NULL;
    }

    if (filename)
	if ((file = open ((char *) filename, O_RDONLY)) == -1) {
/* The file-name is printed after the ':' */
	    edit_error_dialog (_ (" Error "), get_sys_error (catstrs (_ (" Failed trying to open file for reading: "), filename, " ", 0)));
	    return 1;
	}
    edit->curs2 = edit->last_byte;

    buf2 = edit->curs2 >> S_EDIT_BUF_SIZE;

    edit->buffers2[buf2] = CMalloc (EDIT_BUF_SIZE);

    if (filename) {
	readall (file, (char *) edit->buffers2[buf2] + EDIT_BUF_SIZE - (edit->curs2 & M_EDIT_BUF_SIZE), edit->curs2 & M_EDIT_BUF_SIZE);
    } else {
	memcpy (edit->buffers2[buf2] + EDIT_BUF_SIZE - (edit->curs2 & M_EDIT_BUF_SIZE), text, edit->curs2 & M_EDIT_BUF_SIZE);
	text += edit->curs2 & M_EDIT_BUF_SIZE;
    }

    for (buf = buf2 - 1; buf >= 0; buf--) {
	edit->buffers2[buf] = CMalloc (EDIT_BUF_SIZE);
	if (filename) {
	    readall (file, (char *) edit->buffers2[buf], EDIT_BUF_SIZE);
	} else {
	    memcpy (edit->buffers2[buf], text, EDIT_BUF_SIZE);
	    text += EDIT_BUF_SIZE;
	}
    }

    edit->curs1 = 0;
    if (file != -1)
	close (file);
    return 0;
}

/* detecting an error on save is easy: just check if every byte has been written. */
/* detecting an error on read, is not so easy 'cos there is not way to tell
   whether you read everything or not. */
/* FIXME: add proper `triple_pipe_open' to read, write and check errors. */
static struct edit_filters {
    char *read, *write, *extension;
} all_filters[] = {

    {
	"bzip2 -cd %s", "bzip2 > %s", ".bz2"
    },
    {
	"gzip -cd %s", "gzip > %s", ".gz"
    },
    {
	"compress -cd %s", "compress > %s", ".Z"
    }
};

static int edit_find_filter (const char *filename)
{
    int i, l;
    if (!filename)
	return -1;
    l = strlen (filename);
    for (i = 0; i < sizeof (all_filters) / sizeof (struct edit_filters); i++) {
	int e;
	e = strlen (all_filters[i].extension);
	if (l > e)
	    if (!strcmp (all_filters[i].extension, filename + l - e))
		return i;
    }
    return -1;
}

char *edit_get_filter (const char *filename)
{
    int i, l;
    char *p;
    i = edit_find_filter (filename);
    if (i < 0)
	return 0;
    l = strlen (filename);
    p = malloc (strlen (all_filters[i].read) + l + 2);
    sprintf (p, all_filters[i].read, filename);
    return p;
}

char *edit_get_write_filter (char *writename, char *filename)
{
    int i, l;
    char *p;
    i = edit_find_filter (filename);
    if (i < 0)
	return 0;
    l = strlen (writename);
    p = malloc (strlen (all_filters[i].write) + l + 2);
    sprintf (p, all_filters[i].write, writename);
    return p;
}

#ifdef CR_LF_TRANSLATION
/* reads into buffer, replace \r\n with \n */
long edit_insert_stream (WEdit * edit, FILE * f)
{
    int a = -1, b;
    long i;
    while ((b = fgetc (f)) >= 0) {
	if (a == '\r' && b == '\n') {
	    edit_insert (edit, '\n');
	    i++;
	    a = -1;
	    continue;
	} else if (a >= 0) {
	    edit_insert (edit, a);
	    i++;
	}
	a = b;
    }
    if (a >= 0)
	edit_insert (edit, a);
    return i;
}
/* writes buffer, replaces, replace \n with \r\n */
long edit_write_stream (WEdit * edit, FILE * f)
{
    long i;
    int c;
    for (i = 0; i < edit->last_byte; i++) {
	c = edit_get_byte (edit, i);
	if (c == '\n') {
	    if (fputc ('\r', f) < 0)
		break;
	    if (fputc ('\n', f) < 0)
		break;
	} else {
	    if (fputc (c, f) < 0)
		break;
	}
    }
    return i;
}
#else

long edit_insert_stream (WEdit * edit, int fd)
{
    int len;
    long total = 0;
    for (;;) {
	char *p, *q;
	len = 8192;
	q = p = read_pipe (fd, &len);
	if (!len) {
	    free (p);
	    return total;
	}
	total += len;
	while (len--)
	    edit_insert (edit, *p++);
	free (q);
    }
    return total;
}

long edit_write_stream (WEdit * edit, FILE * f)
{
    long i;
    for (i = 0; i < edit->last_byte; i++) {
	int r;
	while ((r = fputc (edit_get_byte (edit, i), f)) == -1 && errno == EINTR);
	if (r < 0)
	    break;
    }
    return i;
}
#endif

#define TEMP_BUF_LEN 1024

/* inserts a file at the cursor, returns 1 on success */
int edit_insert_file (WEdit * edit, const char *filename)
{
    char *p;
    if ((p = edit_get_filter (filename))) {
	long current = edit->curs1;
	int f, g;
	char *a[8];
	a[0] = "/bin/sh";
	a[1] = "-c";
	a[2] = p;
	a[3] = 0;
	if (triple_pipe_open (0, &f, &g, 0, "sh", a) > 0) {
	    edit_insert_stream (edit, f);
	    edit_cursor_move (edit, current - edit->curs1);
	    free (p);
	    p = read_pipe (g, 0);
	    if (strlen (p)) {
		edit_error_dialog (_ (" Error "), catstrs (_ (" Error reading from pipe: "), p, " ", 0));
		free (p);
		close (f);
		close (g);
		return 0;
	    }
	    close (f);
	    close (g);
	} else {
	    edit_error_dialog (_ (" Error "), get_sys_error (catstrs (_ (" Failed trying to open pipe for reading: "), p, " ", 0)));
	    free (p);
	    return 0;
	}
	free (p);
#ifdef CR_LF_TRANSLATION
    } else {
	FILE *f;
	long current = edit->curs1;
	f = fopen (filename, "r");
	if (f) {
	    edit_insert_stream (edit, f);
	    edit_cursor_move (edit, current - edit->curs1);
	    if (fclose (f)) {
		edit_error_dialog (_ (" Error "), get_sys_error (catstrs (_ (" Error reading file: "), filename, " ", 0)));
		return 0;
	    }
	} else {
	    edit_error_dialog (_ (" Error "), get_sys_error (catstrs (_ (" Failed trying to open file for reading: "), filename, " ", 0)));
	    return 0;
	}
#else
    } else {
	int i, file, blocklen;
	long current = edit->curs1;
	unsigned char *buf;
	if ((file = open ((char *) filename, O_RDONLY)) == -1)
	    return 0;
	buf = malloc (TEMP_BUF_LEN);
	while ((blocklen = read (file, (char *) buf, TEMP_BUF_LEN)) > 0) {
	    for (i = 0; i < blocklen; i++)
		edit_insert (edit, buf[i]);
	}
	edit_cursor_move (edit, current - edit->curs1);
	free (buf);
	close (file);
	if (blocklen)
	    return 0;
#endif
    }
    return 1;
}

static int check_file_access (WEdit *edit, const char *filename, struct stat *st)
{
    int file;
#if defined(MIDNIGHT) || defined(GTK)
    if ((file = open ((char *) filename, O_RDONLY)) < 0) {
	close (creat ((char *) filename, 0666));
	if ((file = open ((char *) filename, O_RDONLY)) < 0) {
	    edit_error_dialog (_ (" Error "), get_sys_error (catstrs (" Fail trying to open the file, ", filename, ", for reading ", 0)));
	    return 2;
	}
    }
#else
    if ((file = open ((char *) filename, O_RDONLY)) < 0) {
	edit_error_dialog (_ (" Error "), get_sys_error (catstrs (_ (" Failed trying to open file for reading: "), filename, " ", 0)));
	return 1;
    }
#endif
    if (stat ((char *) filename, st) < 0) {
	close (file);
/* The file-name is printed after the ':' */
	edit_error_dialog (_ (" Error "), get_sys_error (catstrs (_ (" Cannot get size/permissions info on file: "), filename, " ", 0)));
	return 1;
    }
    if (S_ISDIR (st->st_mode) || S_ISSOCK (st->st_mode)
	|| S_ISFIFO (st->st_mode)) {
	close (file);
/* The file-name is printed after the ':' */
	edit_error_dialog (_ (" Error "), catstrs (_ (" Not an ordinary file: "), filename, " ", 0));
	return 1;
    }
    if (st->st_size >= SIZE_LIMIT) {
	close (file);
/* The file-name is printed after the ':' */
	edit_error_dialog (_ (" Error "), catstrs (_ (" File is too large: "), \
						   filename, _ (" \n Increase edit.h:MAXBUF and recompile the editor. "), 0));
	return 1;
    }
    close (file);
    return 0;
}

/* returns 1 on error */
int edit_open_file (WEdit * edit, const char *filename, const char *text, unsigned long text_size)
{
    struct stat st;
    if (text) {
	edit->last_byte = text_size;
	filename = 0;
    } else {
	int r;
	r = check_file_access (edit, filename, &st);
#if defined(MIDNIGHT) || defined(GTK)
	if (r == 2)
	    return edit->delete_file = 1;
#endif
	if (r)
	    return 1;
	edit->stat = st;
#ifndef CR_LF_TRANSLATION
	edit->last_byte = st.st_size;
#else
/* going to read the file into the buffer later byte by byte */
	edit->last_byte = 0;
	filename = 0;
	text = "";
#endif
    }
    return init_dynamic_edit_buffers (edit, filename, text);
}

#ifdef MIDNIGHT
#define space_width 1
#else
int space_width;
extern int option_long_whitespace;

void edit_set_space_width (int s)
{
    space_width = s;
}

#endif

int (*edit_file_is_open) (char *) = 0;

/* fills in the edit struct. returns 0 on fail. Pass edit as NULL for this */
WEdit *edit_init (WEdit * edit, int lines, int columns, const char *filename, const char *text, const char *dir, unsigned long text_size)
{
    char *f;
    int to_free = 0;
    int use_filter = 0;
#ifndef MIDNIGHT
    if (option_long_whitespace)
	edit_set_space_width (FONT_PER_CHAR(' ') * 2);
    else
	edit_set_space_width (FONT_PER_CHAR(' '));
#endif
    if (!edit) {
	edit = malloc (sizeof (WEdit));
	memset (edit, 0, sizeof (WEdit));
	to_free = 1;
    }
    memset (&(edit->from_here), 0, (unsigned long) &(edit->to_here) - (unsigned long) &(edit->from_here));
#ifndef MIDNIGHT
    edit->max_column = columns * FONT_MEAN_WIDTH;
#endif
    edit->num_widget_lines = lines;
    edit->num_widget_columns = columns;