Source:NetHack 3.6.1/src/dlb.c
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Below is the full text to dlb.c from the source code of NetHack 3.6.1. To link to a particular line, write [[Source:NetHack 3.6.1/src/dlb.c#line123]], for example.
Contents
- 1 Top of file
- 2 readlibdir
- 3 find_file
- 4 open_library
- 5 close_library
- 6 lib_dlb_init
- 7 lib_dlb_cleanup
- 8 lib_dlb_fopen
- 9 lib_dlb_fclose
- 10 lib_dlb_fread
- 11 lib_dlb_fseek
- 12 lib_dlb_fgets
- 13 lib_dlb_fgetc
- 14 lib_dlb_ftell
- 15 dlb_init
- 16 dlb_cleanup
- 17 dlb_fopen
- 18 dlb_fclose
- 19 dlb_fread
- 20 dlb_fseek
- 21 dlb_fgets
- 22 dlb_fgetc
- 23 dlb_ftell
Top of file
/* NetHack 3.6 dlb.c $NHDT-Date: 1446975464 2015/11/08 09:37:44 $ $NHDT-Branch: master $:$NHDT-Revision: 1.15 $ */
/* Copyright (c) Kenneth Lorber, Bethesda, Maryland, 1993. */
/* NetHack may be freely redistributed. See license for details. */The NetHack General Public License applies to screenshots, source code and other content from NetHack.
This content was modified from the original NetHack source code distribution (by splitting up NetHack content between wiki pages, and possibly further editing). See the page history for a list of who changed it, and on what dates.
#include "config.h"
#include "dlb.h"
#ifdef __DJGPP__
#include <string.h>
#endif
#define DATAPREFIX 4
#if defined(OVERLAY)
#define STATIC_DCL extern
#define STATIC_OVL
#else /* !OVERLAY */
#define STATIC_DCL static
#define STATIC_OVL static
#endif /* OVERLAY */
#ifdef DLB
/*
* Data librarian. Present a STDIO-like interface to NetHack while
* multiplexing on one or more "data libraries". If a file is not found
* in a given library, look for it outside the libraries.
*/
typedef struct dlb_procs {
boolean NDECL((*dlb_init_proc));
void NDECL((*dlb_cleanup_proc));
boolean FDECL((*dlb_fopen_proc), (DLB_P, const char *, const char *));
int FDECL((*dlb_fclose_proc), (DLB_P));
int FDECL((*dlb_fread_proc), (char *, int, int, DLB_P));
int FDECL((*dlb_fseek_proc), (DLB_P, long, int));
char *FDECL((*dlb_fgets_proc), (char *, int, DLB_P));
int FDECL((*dlb_fgetc_proc), (DLB_P));
long FDECL((*dlb_ftell_proc), (DLB_P));
} dlb_procs_t;
/* without extern.h via hack.h, these haven't been declared for us */
extern FILE *FDECL(fopen_datafile, (const char *, const char *, int));
#ifdef DLBLIB
/*
* Library Implementation:
*
* When initialized, we open all library files and read in their tables
* of contents. The library files stay open all the time. When
* a open is requested, the libraries' directories are searched. If
* successful, we return a descriptor that contains the library, file
* size, and current file mark. This descriptor is used for all
* successive calls.
*
* The ability to open more than one library is supported but used
* only in the Amiga port (the second library holds the sound files).
* For Unix, the idea would be to split the NetHack library
* into text and binary parts, where the text version could be shared.
*/
#define MAX_LIBS 4
static library dlb_libs[MAX_LIBS];
STATIC_DCL boolean FDECL(readlibdir, (library * lp));
STATIC_DCL boolean FDECL(find_file, (const char *name, library **lib,
long *startp, long *sizep));
STATIC_DCL boolean NDECL(lib_dlb_init);
STATIC_DCL void NDECL(lib_dlb_cleanup);
STATIC_DCL boolean FDECL(lib_dlb_fopen, (dlb *, const char *, const char *));
STATIC_DCL int FDECL(lib_dlb_fclose, (dlb *));
STATIC_DCL int FDECL(lib_dlb_fread, (char *, int, int, dlb *));
STATIC_DCL int FDECL(lib_dlb_fseek, (dlb *, long, int));
STATIC_DCL char *FDECL(lib_dlb_fgets, (char *, int, dlb *));
STATIC_DCL int FDECL(lib_dlb_fgetc, (dlb *));
STATIC_DCL long FDECL(lib_dlb_ftell, (dlb *));
/* not static because shared with dlb_main.c */
boolean FDECL(open_library, (const char *lib_name, library *lp));
void FDECL(close_library, (library * lp));
/* without extern.h via hack.h, these haven't been declared for us */
extern char *FDECL(eos, (char *));
/*
* Read the directory out of the library. Return 1 if successful,
* 0 if it failed.
*
* NOTE: An improvement of the file structure should be the file
* size as part of the directory entry or perhaps in place of the
* offset -- the offset can be calculated by a running tally of
* the sizes.
*
* Library file structure:
*
* HEADER:
* %3ld library FORMAT revision (currently rev 1)
* %1c space
* %8ld # of files in archive (includes 1 for directory)
* %1c space
* %8ld size of allocation for string space for directory names
* %1c space
* %8ld library offset - sanity check - lseek target for start of first file
* %1c space
* %8ld size - sanity check - byte size of complete archive file
*
* followed by one DIRECTORY entry for each file in the archive, including
* the directory itself:
* %1c handling information (compression, etc.) Always ' ' in rev 1.
* %s file name
* %1c space
* %8ld offset in archive file of start of this file
* %c newline
*
* followed by the contents of the files
*/
#define DLB_MIN_VERS 1 /* min library version readable by this code */
#define DLB_MAX_VERS 1 /* max library version readable by this code */
readlibdir
/*
* Read the directory from the library file. This will allocate and
* fill in our globals. The file pointer is reset back to position
* zero. If any part fails, leave nothing that needs to be deallocated.
*
* Return TRUE on success, FALSE on failure.
*/
STATIC_OVL boolean
readlibdir(lp)
library *lp; /* library pointer to fill in */
{
int i;
char *sp;
long liboffset, totalsize;
if (fscanf(lp->fdata, "%ld %ld %ld %ld %ld\n", &lp->rev, &lp->nentries,
&lp->strsize, &liboffset, &totalsize) != 5)
return FALSE;
if (lp->rev > DLB_MAX_VERS || lp->rev < DLB_MIN_VERS)
return FALSE;
lp->dir = (libdir *) alloc(lp->nentries * sizeof(libdir));
lp->sspace = (char *) alloc(lp->strsize);
/* read in each directory entry */
for (i = 0, sp = lp->sspace; i < lp->nentries; i++) {
lp->dir[i].fname = sp;
if (fscanf(lp->fdata, "%c%s %ld\n", &lp->dir[i].handling, sp,
&lp->dir[i].foffset) != 3) {
free((genericptr_t) lp->dir);
free((genericptr_t) lp->sspace);
lp->dir = (libdir *) 0;
lp->sspace = (char *) 0;
return FALSE;
}
sp = eos(sp) + 1;
}
/* calculate file sizes using offset information */
for (i = 0; i < lp->nentries; i++) {
if (i == lp->nentries - 1)
lp->dir[i].fsize = totalsize - lp->dir[i].foffset;
else
lp->dir[i].fsize = lp->dir[i + 1].foffset - lp->dir[i].foffset;
}
(void) fseek(lp->fdata, 0L, SEEK_SET); /* reset back to zero */
lp->fmark = 0;
return TRUE;
}
find_file
/*
* Look for the file in our directory structure. Return 1 if successful,
* 0 if not found. Fill in the size and starting position.
*/
STATIC_OVL boolean
find_file(name, lib, startp, sizep)
const char *name;
library **lib;
long *startp, *sizep;
{
int i, j;
library *lp;
for (i = 0; i < MAX_LIBS && dlb_libs[i].fdata; i++) {
lp = &dlb_libs[i];
for (j = 0; j < lp->nentries; j++) {
if (FILENAME_CMP(name, lp->dir[j].fname) == 0) {
*lib = lp;
*startp = lp->dir[j].foffset;
*sizep = lp->dir[j].fsize;
return TRUE;
}
}
}
*lib = (library *) 0;
*startp = *sizep = 0;
return FALSE;
}
open_library
/*
* Open the library of the given name and fill in the given library
* structure. Return TRUE if successful, FALSE otherwise.
*/
boolean
open_library(lib_name, lp)
const char *lib_name;
library *lp;
{
boolean status = FALSE;
lp->fdata = fopen_datafile(lib_name, RDBMODE, DATAPREFIX);
if (lp->fdata) {
if (readlibdir(lp)) {
status = TRUE;
} else {
(void) fclose(lp->fdata);
lp->fdata = (FILE *) 0;
}
}
return status;
}
close_library
void
close_library(lp)
library *lp;
{
(void) fclose(lp->fdata);
free((genericptr_t) lp->dir);
free((genericptr_t) lp->sspace);
(void) memset((char *) lp, 0, sizeof(library));
}
lib_dlb_init
/*
* Open the library file once using stdio. Keep it open, but
* keep track of the file position.
*/
STATIC_OVL boolean
lib_dlb_init(VOID_ARGS)
{
/* zero out array */
(void) memset((char *) &dlb_libs[0], 0, sizeof(dlb_libs));
/* To open more than one library, add open library calls here. */
if (!open_library(DLBFILE, &dlb_libs[0]))
return FALSE;
#ifdef DLBFILE2
if (!open_library(DLBFILE2, &dlb_libs[1])) {
close_library(&dlb_libs[0]);
return FALSE;
}
#endif
return TRUE;
}
lib_dlb_cleanup
STATIC_OVL void
lib_dlb_cleanup(VOID_ARGS)
{
int i;
/* close the data file(s) */
for (i = 0; i < MAX_LIBS && dlb_libs[i].fdata; i++)
close_library(&dlb_libs[i]);
}
/*ARGSUSED*/lib_dlb_fopen
STATIC_OVL boolean
lib_dlb_fopen(dp, name, mode)
dlb *dp;
const char *name;
const char *mode UNUSED;
{
long start, size;
library *lp;
/* look up file in directory */
if (find_file(name, &lp, &start, &size)) {
dp->lib = lp;
dp->start = start;
dp->size = size;
dp->mark = 0;
return TRUE;
}
return FALSE; /* failed */
}
/*ARGUSED*/lib_dlb_fclose
STATIC_OVL int
lib_dlb_fclose(dp)
dlb *dp UNUSED;
{
/* nothing needs to be done */
return 0;
}
lib_dlb_fread
STATIC_OVL int
lib_dlb_fread(buf, size, quan, dp)
char *buf;
int size, quan;
dlb *dp;
{
long pos, nread, nbytes;
/* make sure we don't read into the next file */
if ((dp->size - dp->mark) < (size * quan))
quan = (dp->size - dp->mark) / size;
if (quan == 0)
return 0;
pos = dp->start + dp->mark;
if (dp->lib->fmark != pos) {
fseek(dp->lib->fdata, pos, SEEK_SET); /* check for error??? */
dp->lib->fmark = pos;
}
nread = fread(buf, size, quan, dp->lib->fdata);
nbytes = nread * size;
dp->mark += nbytes;
dp->lib->fmark += nbytes;
return nread;
}
lib_dlb_fseek
STATIC_OVL int
lib_dlb_fseek(dp, pos, whence)
dlb *dp;
long pos;
int whence;
{
long curpos;
switch (whence) {
case SEEK_CUR:
curpos = dp->mark + pos;
break;
case SEEK_END:
curpos = dp->size - pos;
break;
default: /* set */
curpos = pos;
break;
}
if (curpos < 0)
curpos = 0;
if (curpos > dp->size)
curpos = dp->size;
dp->mark = curpos;
return 0;
}
lib_dlb_fgets
STATIC_OVL char *
lib_dlb_fgets(buf, len, dp)
char *buf;
int len;
dlb *dp;
{
int i;
char *bp, c = 0;
if (len <= 0)
return buf; /* sanity check */
/* return NULL on EOF */
if (dp->mark >= dp->size)
return (char *) 0;
len--; /* save room for null */
for (i = 0, bp = buf; i < len && dp->mark < dp->size && c != '\n';
i++, bp++) {
if (dlb_fread(bp, 1, 1, dp) <= 0)
break; /* EOF or error */
c = *bp;
}
*bp = '\0';
#if defined(MSDOS) || defined(WIN32)
if ((bp = index(buf, '\r')) != 0) {
*bp++ = '\n';
*bp = '\0';
}
#endif
return buf;
}
lib_dlb_fgetc
STATIC_OVL int
lib_dlb_fgetc(dp)
dlb *dp;
{
char c;
if (lib_dlb_fread(&c, 1, 1, dp) != 1)
return EOF;
return (int) c;
}
lib_dlb_ftell
STATIC_OVL long
lib_dlb_ftell(dp)
dlb *dp;
{
return dp->mark;
}
const dlb_procs_t lib_dlb_procs = { lib_dlb_init, lib_dlb_cleanup,
lib_dlb_fopen, lib_dlb_fclose,
lib_dlb_fread, lib_dlb_fseek,
lib_dlb_fgets, lib_dlb_fgetc,
lib_dlb_ftell };
#endif /* DLBLIB */
#ifdef DLBRSRC
const dlb_procs_t rsrc_dlb_procs = { rsrc_dlb_init, rsrc_dlb_cleanup,
rsrc_dlb_fopen, rsrc_dlb_fclose,
rsrc_dlb_fread, rsrc_dlb_fseek,
rsrc_dlb_fgets, rsrc_dlb_fgetc,
rsrc_dlb_ftell };
#endif
/* Global wrapper functions ------------------------------------------------
*/
#define do_dlb_init (*dlb_procs->dlb_init_proc)
#define do_dlb_cleanup (*dlb_procs->dlb_cleanup_proc)
#define do_dlb_fopen (*dlb_procs->dlb_fopen_proc)
#define do_dlb_fclose (*dlb_procs->dlb_fclose_proc)
#define do_dlb_fread (*dlb_procs->dlb_fread_proc)
#define do_dlb_fseek (*dlb_procs->dlb_fseek_proc)
#define do_dlb_fgets (*dlb_procs->dlb_fgets_proc)
#define do_dlb_fgetc (*dlb_procs->dlb_fgetc_proc)
#define do_dlb_ftell (*dlb_procs->dlb_ftell_proc)
static const dlb_procs_t *dlb_procs;
static boolean dlb_initialized = FALSE;
dlb_init
boolean
dlb_init()
{
if (!dlb_initialized) {
#ifdef DLBLIB
dlb_procs = &lib_dlb_procs;
#endif
#ifdef DLBRSRC
dlb_procs = &rsrc_dlb_procs;
#endif
if (dlb_procs)
dlb_initialized = do_dlb_init();
}
return dlb_initialized;
}
dlb_cleanup
void
dlb_cleanup()
{
if (dlb_initialized) {
do_dlb_cleanup();
dlb_initialized = FALSE;
}
}
dlb_fopen
dlb *
dlb_fopen(name, mode)
const char *name, *mode;
{
FILE *fp;
dlb *dp;
if (!dlb_initialized)
return (dlb *) 0;
/* only support reading; ignore possible binary flag */
if (!mode || mode[0] != 'r')
return (dlb *) 0;
dp = (dlb *) alloc(sizeof(dlb));
if (do_dlb_fopen(dp, name, mode))
dp->fp = (FILE *) 0;
else if ((fp = fopen_datafile(name, mode, DATAPREFIX)) != 0)
dp->fp = fp;
else {
/* can't find anything */
free((genericptr_t) dp);
dp = (dlb *) 0;
}
return dp;
}
dlb_fclose
int
dlb_fclose(dp)
dlb *dp;
{
int ret = 0;
if (dlb_initialized) {
if (dp->fp)
ret = fclose(dp->fp);
else
ret = do_dlb_fclose(dp);
free((genericptr_t) dp);
}
return ret;
}
dlb_fread
int
dlb_fread(buf, size, quan, dp)
char *buf;
int size, quan;
dlb *dp;
{
if (!dlb_initialized || size <= 0 || quan <= 0)
return 0;
if (dp->fp)
return (int) fread(buf, size, quan, dp->fp);
return do_dlb_fread(buf, size, quan, dp);
}
dlb_fseek
int
dlb_fseek(dp, pos, whence)
dlb *dp;
long pos;
int whence;
{
if (!dlb_initialized)
return EOF;
if (dp->fp)
return fseek(dp->fp, pos, whence);
return do_dlb_fseek(dp, pos, whence);
}
dlb_fgets
char *
dlb_fgets(buf, len, dp)
char *buf;
int len;
dlb *dp;
{
if (!dlb_initialized)
return (char *) 0;
if (dp->fp)
return fgets(buf, len, dp->fp);
return do_dlb_fgets(buf, len, dp);
}
dlb_fgetc
int
dlb_fgetc(dp)
dlb *dp;
{
if (!dlb_initialized)
return EOF;
if (dp->fp)
return fgetc(dp->fp);
return do_dlb_fgetc(dp);
}
dlb_ftell
long
dlb_ftell(dp)
dlb *dp;
{
if (!dlb_initialized)
return 0;
if (dp->fp)
return ftell(dp->fp);
return do_dlb_ftell(dp);
}
#endif /* DLB */
/*dlb.c*/