read_ent.c

来自「开放源码的编译器open watcom 1.6.0版的源代码」· C语言 代码 · 共 504 行 · 第 1/2 页

/****************************************************************************
 * Copyright (c) 1998,1999,2000 Free Software Foundation, Inc.              *
 *                                                                          *
 * Permission is hereby granted, free of charge, to any person obtaining a  *
 * copy of this software and associated documentation files (the            *
 * "Software"), to deal in the Software without restriction, including      *
 * without limitation the rights to use, copy, modify, merge, publish,      *
 * distribute, distribute with modifications, sublicense, and/or sell       *
 * copies of the Software, and to permit persons to whom the Software is    *
 * furnished to do so, subject to the following conditions:                 *
 *                                                                          *
 * The above copyright notice and this permission notice shall be included  *
 * in all copies or substantial portions of the Software.                   *
 *                                                                          *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
 * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
 *                                                                          *
 * Except as contained in this notice, the name(s) of the above copyright   *
 * holders shall not be used in advertising or otherwise to promote the     *
 * sale, use or other dealings in this Software without prior written       *
 * authorization.                                                           *
 ****************************************************************************/

/****************************************************************************
 *  Author: Zeyd M. Ben-Halim <[e-mail]> 1992,1995               *
 *     and: Eric S. Raymond <[e-mail]>                         *
 ****************************************************************************/

/*
 *	read_entry.c -- Routine for reading in a compiled terminfo file
 *
 */

#include <curses_p.h>

#include <tic.h>
#include <term_ent.h>

MODULE_ID("$Id: read_entry.c,v 1.72 2000/12/10 02:55:08 tom Exp $")

#if !HAVE_TELL
#define tell(fd) 0		/* lseek() is POSIX, but not tell() - odd... */
#endif

/*
 *	int
 *	_nc_read_file_entry(filename, ptr)
 *
 *	Read the compiled terminfo entry in the given file into the
 *	structure pointed to by ptr, allocating space for the string
 *	table.
 */

#undef  BYTE
#define BYTE(p,n)	(unsigned char)((p)[n])

#define IS_NEG1(p)	((BYTE(p,0) == 0377) && (BYTE(p,1) == 0377))
#define IS_NEG2(p)	((BYTE(p,0) == 0376) && (BYTE(p,1) == 0377))
#define LOW_MSB(p)	(BYTE(p,0) + 256*BYTE(p,1))

static bool have_tic_directory = FALSE;
static bool keep_tic_directory = FALSE;

/*
 * Record the "official" location of the terminfo directory, according to
 * the place where we're writing to, or the normal default, if not.
 */
NCURSES_EXPORT(const char *)
_nc_tic_dir(const char *path)
{
    static const char *result = TERMINFO;

    if (!keep_tic_directory) {
	if (path != 0) {
	    result = path;
	    have_tic_directory = TRUE;
	} else if (!have_tic_directory && use_terminfo_vars()) {
	    char *envp;
	    if ((envp = getenv("TERMINFO")) != 0)
		return _nc_tic_dir(envp);
	}
    }
    return result;
}

/*
 * Special fix to prevent the terminfo directory from being moved after tic
 * has chdir'd to it.  If we let it be changed, then if $TERMINFO has a
 * relative path, we'll lose track of the actual directory.
 */
NCURSES_EXPORT(void)
_nc_keep_tic_dir(const char *path)
{
    _nc_tic_dir(path);
    keep_tic_directory = TRUE;
}

static void
convert_shorts(char *buf, short *Numbers, int count)
{
    int i;
    for (i = 0; i < count; i++) {
	if (IS_NEG1(buf + 2 * i))
	    Numbers[i] = ABSENT_NUMERIC;
	else if (IS_NEG2(buf + 2 * i))
	    Numbers[i] = CANCELLED_NUMERIC;
	else
	    Numbers[i] = LOW_MSB(buf + 2 * i);
	TR(TRACE_DATABASE, ("get Numbers[%d]=%d", i, Numbers[i]));
    }
}

static void
convert_strings(char *buf, char **Strings, int count, int size, char *table)
{
    int i;
    char *p;

    for (i = 0; i < count; i++) {
	if (IS_NEG1(buf + 2 * i)) {
	    Strings[i] = ABSENT_STRING;
	} else if (IS_NEG2(buf + 2 * i)) {
	    Strings[i] = CANCELLED_STRING;
	} else if (LOW_MSB(buf + 2 * i) > size) {
	    Strings[i] = ABSENT_STRING;
	} else {
	    Strings[i] = (LOW_MSB(buf + 2 * i) + table);
	    TR(TRACE_DATABASE, ("Strings[%d] = %s", i, _nc_visbuf(Strings[i])));
	}

	/* make sure all strings are NUL terminated */
	if (VALID_STRING(Strings[i])) {
	    for (p = Strings[i]; p <= table + size; p++)
		if (*p == '\0')
		    break;
	    /* if there is no NUL, ignore the string */
	    if (p > table + size)
		Strings[i] = ABSENT_STRING;
	}
    }
}

#define read_shorts(fd, buf, count) (read(fd, buf, (count)*2) == (count)*2)

#define even_boundary(value) \
    if ((value) % 2 != 0) read(fd, buf, 1)

static int
read_termtype(int fd, TERMTYPE * ptr)
/* return 1 if read, 0 if not found or garbled */
{
    int name_size, bool_count, num_count, str_count, str_size;
    int i;
    char buf[MAX_ENTRY_SIZE];

    TR(TRACE_DATABASE, ("READ termtype header @%d", tell(fd)));

    memset(ptr, 0, sizeof(*ptr));

    /* grab the header */
    if (!read_shorts(fd, buf, 6)
	|| LOW_MSB(buf) != MAGIC) {
	return (0);
    }

    _nc_free_termtype(ptr);
    name_size = LOW_MSB(buf + 2);
    bool_count = LOW_MSB(buf + 4);
    num_count = LOW_MSB(buf + 6);
    str_count = LOW_MSB(buf + 8);
    str_size = LOW_MSB(buf + 10);

    TR(TRACE_DATABASE,
       ("TERMTYPE name_size=%d, bool=%d/%d, num=%d/%d str=%d/%d(%d)",
	name_size, bool_count, BOOLCOUNT, num_count, NUMCOUNT,
	str_count, STRCOUNT, str_size));
    if (name_size < 0
	|| bool_count < 0
	|| num_count < 0
	|| str_count < 0
	|| str_size < 0) {
	return (0);
    }

    if (str_size) {
	/* try to allocate space for the string table */
	if (str_count * 2 >= (int) sizeof(buf)
	    || (ptr->str_table = typeMalloc(char, (unsigned) str_size)) == 0) {
	    return (0);
	}
    } else {
	str_count = 0;
    }

    /* grab the name (a null-terminate string) */
    read(fd, buf, min(MAX_NAME_SIZE, (unsigned) name_size));
    buf[MAX_NAME_SIZE] = '\0';
    ptr->term_names = typeCalloc(char, strlen(buf) + 1);
    if (ptr->term_names == NULL) {
	return (0);
    }
    (void) strcpy(ptr->term_names, buf);
    if (name_size > MAX_NAME_SIZE)
	lseek(fd, (off_t) (name_size - MAX_NAME_SIZE), 1);

    /* grab the booleans */
    if ((ptr->Booleans = typeCalloc(char, max(BOOLCOUNT, bool_count))) == 0
	|| read(fd, ptr->Booleans, (unsigned) bool_count) < bool_count) {
	return (0);
    }

    /*
     * If booleans end on an odd byte, skip it.  The machine they
     * originally wrote terminfo on must have been a 16-bit
     * word-oriented machine that would trap out if you tried a
     * word access off a 2-byte boundary.
     */
    even_boundary(name_size + bool_count);

    /* grab the numbers */
    if ((ptr->Numbers = typeCalloc(short, max(NUMCOUNT, num_count))) == 0
	|| !read_shorts(fd, buf, num_count)) {
	return (0);
    }
    convert_shorts(buf, ptr->Numbers, num_count);

    if ((ptr->Strings = typeCalloc(char *, max(STRCOUNT, str_count))) == 0)
	  return (0);

    if (str_count) {
	/* grab the string offsets */
	if (!read_shorts(fd, buf, str_count)) {
	    return (0);
	}
	/* finally, grab the string table itself */
	if (read(fd, ptr->str_table, (unsigned) str_size) != str_size)
	    return (0);
	convert_strings(buf, ptr->Strings, str_count, str_size, ptr->str_table);
    }
#if NCURSES_XNAMES

    ptr->num_Booleans = BOOLCOUNT;
    ptr->num_Numbers = NUMCOUNT;
    ptr->num_Strings = STRCOUNT;

    /*
     * Read extended entries, if any, after the normal end of terminfo data.