1b28029810
distributed under your choice of the GPL or a BSD style license. Reviewed by: peter Obtained from: http://home.flash.net/~marknu/less/
347 lines
6.3 KiB
C
347 lines
6.3 KiB
C
/*
|
|
* Copyright (C) 1984-2000 Mark Nudelman
|
|
*
|
|
* You may distribute under the terms of either the GNU General Public
|
|
* License or the Less License, as specified in the README file.
|
|
*
|
|
* For more information about less, or for information on how to
|
|
* contact the author, see the README file.
|
|
*/
|
|
|
|
|
|
/*
|
|
* An IFILE represents an input file.
|
|
*
|
|
* It is actually a pointer to an ifile structure,
|
|
* but is opaque outside this module.
|
|
* Ifile structures are kept in a linked list in the order they
|
|
* appear on the command line.
|
|
* Any new file which does not already appear in the list is
|
|
* inserted after the current file.
|
|
*/
|
|
|
|
#include "less.h"
|
|
|
|
extern IFILE curr_ifile;
|
|
|
|
struct ifile {
|
|
struct ifile *h_next; /* Links for command line list */
|
|
struct ifile *h_prev;
|
|
char *h_filename; /* Name of the file */
|
|
void *h_filestate; /* File state (used in ch.c) */
|
|
int h_index; /* Index within command line list */
|
|
int h_hold; /* Hold count */
|
|
char h_opened; /* Has this ifile been opened? */
|
|
struct scrpos h_scrpos; /* Saved position within the file */
|
|
};
|
|
|
|
/*
|
|
* Convert an IFILE (external representation)
|
|
* to a struct file (internal representation), and vice versa.
|
|
*/
|
|
#define int_ifile(h) ((struct ifile *)(h))
|
|
#define ext_ifile(h) ((IFILE)(h))
|
|
|
|
/*
|
|
* Anchor for linked list.
|
|
*/
|
|
static struct ifile anchor = { &anchor, &anchor, NULL, NULL, 0, 0, '\0',
|
|
{ NULL_POSITION, 0 } };
|
|
static int ifiles = 0;
|
|
|
|
static void
|
|
incr_index(p, incr)
|
|
register struct ifile *p;
|
|
int incr;
|
|
{
|
|
for (; p != &anchor; p = p->h_next)
|
|
p->h_index += incr;
|
|
}
|
|
|
|
/*
|
|
* Link an ifile into the ifile list.
|
|
*/
|
|
static void
|
|
link_ifile(p, prev)
|
|
struct ifile *p;
|
|
struct ifile *prev;
|
|
{
|
|
/*
|
|
* Link into list.
|
|
*/
|
|
if (prev == NULL)
|
|
prev = &anchor;
|
|
p->h_next = prev->h_next;
|
|
p->h_prev = prev;
|
|
prev->h_next->h_prev = p;
|
|
prev->h_next = p;
|
|
/*
|
|
* Calculate index for the new one,
|
|
* and adjust the indexes for subsequent ifiles in the list.
|
|
*/
|
|
p->h_index = prev->h_index + 1;
|
|
incr_index(p->h_next, 1);
|
|
ifiles++;
|
|
}
|
|
|
|
/*
|
|
* Unlink an ifile from the ifile list.
|
|
*/
|
|
static void
|
|
unlink_ifile(p)
|
|
struct ifile *p;
|
|
{
|
|
p->h_next->h_prev = p->h_prev;
|
|
p->h_prev->h_next = p->h_next;
|
|
incr_index(p->h_next, -1);
|
|
ifiles--;
|
|
}
|
|
|
|
/*
|
|
* Allocate a new ifile structure and stick a filename in it.
|
|
* It should go after "prev" in the list
|
|
* (or at the beginning of the list if "prev" is NULL).
|
|
* Return a pointer to the new ifile structure.
|
|
*/
|
|
static struct ifile *
|
|
new_ifile(filename, prev)
|
|
char *filename;
|
|
struct ifile *prev;
|
|
{
|
|
register struct ifile *p;
|
|
|
|
/*
|
|
* Allocate and initialize structure.
|
|
*/
|
|
p = (struct ifile *) ecalloc(1, sizeof(struct ifile));
|
|
p->h_filename = save(filename);
|
|
p->h_scrpos.pos = NULL_POSITION;
|
|
p->h_opened = 0;
|
|
p->h_hold = 0;
|
|
p->h_filestate = NULL;
|
|
link_ifile(p, prev);
|
|
return (p);
|
|
}
|
|
|
|
/*
|
|
* Delete an existing ifile structure.
|
|
*/
|
|
public void
|
|
del_ifile(h)
|
|
IFILE h;
|
|
{
|
|
register struct ifile *p;
|
|
|
|
if (h == NULL_IFILE)
|
|
return;
|
|
/*
|
|
* If the ifile we're deleting is the currently open ifile,
|
|
* move off it.
|
|
*/
|
|
unmark(h);
|
|
if (h == curr_ifile)
|
|
curr_ifile = getoff_ifile(curr_ifile);
|
|
p = int_ifile(h);
|
|
unlink_ifile(p);
|
|
free(p->h_filename);
|
|
free(p);
|
|
}
|
|
|
|
/*
|
|
* Get the ifile after a given one in the list.
|
|
*/
|
|
public IFILE
|
|
next_ifile(h)
|
|
IFILE h;
|
|
{
|
|
register struct ifile *p;
|
|
|
|
p = (h == NULL_IFILE) ? &anchor : int_ifile(h);
|
|
if (p->h_next == &anchor)
|
|
return (NULL_IFILE);
|
|
return (ext_ifile(p->h_next));
|
|
}
|
|
|
|
/*
|
|
* Get the ifile before a given one in the list.
|
|
*/
|
|
public IFILE
|
|
prev_ifile(h)
|
|
IFILE h;
|
|
{
|
|
register struct ifile *p;
|
|
|
|
p = (h == NULL_IFILE) ? &anchor : int_ifile(h);
|
|
if (p->h_prev == &anchor)
|
|
return (NULL_IFILE);
|
|
return (ext_ifile(p->h_prev));
|
|
}
|
|
|
|
/*
|
|
* Return a different ifile from the given one.
|
|
*/
|
|
public IFILE
|
|
getoff_ifile(ifile)
|
|
IFILE ifile;
|
|
{
|
|
IFILE newifile;
|
|
|
|
if ((newifile = prev_ifile(ifile)) != NULL_IFILE)
|
|
return (newifile);
|
|
if ((newifile = next_ifile(ifile)) != NULL_IFILE)
|
|
return (newifile);
|
|
return (NULL_IFILE);
|
|
}
|
|
|
|
/*
|
|
* Return the number of ifiles.
|
|
*/
|
|
public int
|
|
nifile()
|
|
{
|
|
return (ifiles);
|
|
}
|
|
|
|
/*
|
|
* Find an ifile structure, given a filename.
|
|
*/
|
|
static struct ifile *
|
|
find_ifile(filename)
|
|
char *filename;
|
|
{
|
|
register struct ifile *p;
|
|
|
|
for (p = anchor.h_next; p != &anchor; p = p->h_next)
|
|
if (strcmp(filename, p->h_filename) == 0)
|
|
return (p);
|
|
return (NULL);
|
|
}
|
|
|
|
/*
|
|
* Get the ifile associated with a filename.
|
|
* If the filename has not been seen before,
|
|
* insert the new ifile after "prev" in the list.
|
|
*/
|
|
public IFILE
|
|
get_ifile(filename, prev)
|
|
char *filename;
|
|
IFILE prev;
|
|
{
|
|
register struct ifile *p;
|
|
|
|
if ((p = find_ifile(filename)) == NULL)
|
|
p = new_ifile(filename, int_ifile(prev));
|
|
return (ext_ifile(p));
|
|
}
|
|
|
|
/*
|
|
* Get the filename associated with a ifile.
|
|
*/
|
|
public char *
|
|
get_filename(ifile)
|
|
IFILE ifile;
|
|
{
|
|
if (ifile == NULL)
|
|
return (NULL);
|
|
return (int_ifile(ifile)->h_filename);
|
|
}
|
|
|
|
/*
|
|
* Get the index of the file associated with a ifile.
|
|
*/
|
|
public int
|
|
get_index(ifile)
|
|
IFILE ifile;
|
|
{
|
|
return (int_ifile(ifile)->h_index);
|
|
}
|
|
|
|
/*
|
|
* Save the file position to be associated with a given file.
|
|
*/
|
|
public void
|
|
store_pos(ifile, scrpos)
|
|
IFILE ifile;
|
|
struct scrpos *scrpos;
|
|
{
|
|
int_ifile(ifile)->h_scrpos = *scrpos;
|
|
}
|
|
|
|
/*
|
|
* Recall the file position associated with a file.
|
|
* If no position has been associated with the file, return NULL_POSITION.
|
|
*/
|
|
public void
|
|
get_pos(ifile, scrpos)
|
|
IFILE ifile;
|
|
struct scrpos *scrpos;
|
|
{
|
|
*scrpos = int_ifile(ifile)->h_scrpos;
|
|
}
|
|
|
|
/*
|
|
* Mark the ifile as "opened".
|
|
*/
|
|
public void
|
|
set_open(ifile)
|
|
IFILE ifile;
|
|
{
|
|
int_ifile(ifile)->h_opened = 1;
|
|
}
|
|
|
|
/*
|
|
* Return whether the ifile has been opened previously.
|
|
*/
|
|
public int
|
|
opened(ifile)
|
|
IFILE ifile;
|
|
{
|
|
return (int_ifile(ifile)->h_opened);
|
|
}
|
|
|
|
public void
|
|
hold_ifile(ifile, incr)
|
|
IFILE ifile;
|
|
int incr;
|
|
{
|
|
int_ifile(ifile)->h_hold += incr;
|
|
}
|
|
|
|
public int
|
|
held_ifile(ifile)
|
|
IFILE ifile;
|
|
{
|
|
return (int_ifile(ifile)->h_hold);
|
|
}
|
|
|
|
public void *
|
|
get_filestate(ifile)
|
|
IFILE ifile;
|
|
{
|
|
return (int_ifile(ifile)->h_filestate);
|
|
}
|
|
|
|
public void
|
|
set_filestate(ifile, filestate)
|
|
IFILE ifile;
|
|
void *filestate;
|
|
{
|
|
int_ifile(ifile)->h_filestate = filestate;
|
|
}
|
|
|
|
#if 0
|
|
public void
|
|
if_dump()
|
|
{
|
|
register struct ifile *p;
|
|
|
|
for (p = anchor.h_next; p != &anchor; p = p->h_next)
|
|
{
|
|
printf("%x: %d. <%s> pos %d,%x\n",
|
|
p, p->h_index, p->h_filename,
|
|
p->h_scrpos.ln, p->h_scrpos.pos);
|
|
ch_dump(p->h_filestate);
|
|
}
|
|
}
|
|
#endif
|