minix/commands/elvis/cut.c
2005-04-21 14:53:53 +00:00

700 lines
13 KiB
C
Executable file

/* cut.c */
/* Author:
* Steve Kirkendall
* 14407 SW Teal Blvd. #C
* Beaverton, OR 97005
* kirkenda@cs.pdx.edu
*/
/* This file contains function which manipulate the cut buffers. */
#include "config.h"
#include "vi.h"
#if TURBOC
#include <process.h> /* needed for getpid */
#endif
#if TOS
#include <osbind.h>
#define rename(a,b) Frename(0,a,b)
#endif
# define NANONS 9 /* number of anonymous buffers */
static struct cutbuf
{
short *phys; /* pointer to an array of #s of BLKs containing text */
int nblks; /* number of blocks in phys[] array */
int start; /* offset into first block of start of cut */
int end; /* offset into last block of end of cut */
int tmpnum; /* ID number of the temp file */
char lnmode; /* boolean: line-mode cut? (as opposed to char-mode) */
}
named[27], /* cut buffers "a through "z and ". */
anon[NANONS]; /* anonymous cut buffers */
static char cbname; /* name chosen for next cut/paste operation */
static char dotcb; /* cut buffer to use if "doingdot" is set */
#ifndef NO_RECYCLE
/* This function builds a list of all blocks needed in the current tmp file
* for the contents of cut buffers.
* !!! WARNING: if you have more than ~450000 bytes of text in all of the
* cut buffers, then this will fail disastrously, because buffer overflow
* is *not* allowed for.
*/
int cutneeds(need)
BLK *need; /* this is where we deposit the list */
{
struct cutbuf *cb; /* used to count through cut buffers */
int i; /* used to count through blocks of a cut buffer */
int n; /* total number of blocks in list */
n = 0;
/* first the named buffers... */
for (cb = named; cb < &named[27]; cb++)
{
if (cb->tmpnum != tmpnum)
continue;
for (i = cb->nblks; i-- > 0; )
{
need->n[n++] = cb->phys[i];
}
}
/* then the anonymous buffers */
for (cb = anon; cb < &anon[NANONS]; cb++)
{
if (cb->tmpnum != tmpnum)
continue;
for (i = cb->nblks; i-- > 0; )
{
need->n[n++] = cb->phys[i];
}
}
/* return the length of the list */
return n;
}
#endif
static void maybezap(num)
int num; /* the tmpnum of the temporary file to [maybe] delete */
{
char cutfname[80];
int i;
/* if this is the current tmp file, then we'd better keep it! */
if (tmpfd >= 0 && num == tmpnum)
{
return;
}
/* see if anybody else needs this tmp file */
for (i = 27; --i >= 0; )
{
if (named[i].nblks > 0 && named[i].tmpnum == num)
{
break;
}
}
if (i < 0)
{
for (i = NANONS; --i >= 0 ; )
{
if (anon[i].nblks > 0 && anon[i].tmpnum == num)
{
break;
}
}
}
/* if nobody else needs it, then discard the tmp file */
if (i < 0)
{
#if MSDOS || TOS
strcpy(cutfname, o_directory);
if ((i = strlen(cutfname)) && !strchr(":/\\", cutfname[i - 1]))
cutfname[i++] = SLASH;
sprintf(cutfname + i, TMPNAME + 3, getpid(), num);
#else
sprintf(cutfname, TMPNAME, o_directory, getpid(), num);
#endif
unlink(cutfname);
}
}
/* This function frees a cut buffer. If it was the last cut buffer that
* refered to an old temp file, then it will delete the temp file. */
static void cutfree(buf)
struct cutbuf *buf;
{
int num;
/* return immediately if the buffer is already empty */
if (buf->nblks <= 0)
{
return;
}
/* else free up stuff */
num = buf->tmpnum;
buf->nblks = 0;
#ifdef DEBUG
if (!buf->phys)
msg("cutfree() tried to free a NULL buf->phys pointer.");
else
#endif
free((char *)buf->phys);
/* maybe delete the temp file */
maybezap(num);
}
/* This function is called when we are about to abort a tmp file.
*
* To minimize the number of extra files lying around, only named cut buffers
* are preserved in a file switch; the anonymous buffers just go away.
*/
void cutswitch()
{
int i;
/* mark the current temp file as being "obsolete", and close it. */
storename((char *)0);
close(tmpfd);
tmpfd = -1;
/* discard all anonymous cut buffers */
for (i = 0; i < NANONS; i++)
{
cutfree(&anon[i]);
}
/* delete the temp file, if we don't really need it */
maybezap(tmpnum);
}
/* This function should be called just before termination of vi */
void cutend()
{
int i;
/* free the anonymous buffers, if they aren't already free */
cutswitch();
/* free all named cut buffers, since they might be forcing an older
* tmp file to be retained.
*/
for (i = 0; i < 27; i++)
{
cutfree(&named[i]);
}
/* delete the temp file */
maybezap(tmpnum);
}
/* This function is used to select the cut buffer to be used next */
void cutname(name)
int name; /* a single character */
{
cbname = name;
}
/* This function copies a selected segment of text to a cut buffer */
void cut(from, to)
MARK from; /* start of text to cut */
MARK to; /* end of text to cut */
{
int first; /* logical number of first block in cut */
int last; /* logical number of last block used in cut */
long line; /* a line number */
int lnmode; /* boolean: will this be a line-mode cut? */
MARK delthru;/* end of text temporarily inserted for apnd */
REG struct cutbuf *cb;
REG long l;
REG int i;
REG char *scan;
char *blkc;
/* detect whether this must be a line-mode cut or char-mode cut */
if (markidx(from) == 0 && markidx(to) == 0)
lnmode = TRUE;
else
lnmode = FALSE;
/* by default, we don't "delthru" anything */
delthru = MARK_UNSET;
/* handle the "doingdot" quirks */
if (doingdot)
{
if (!cbname)
{
cbname = dotcb;
}
}
else if (cbname != '.')
{
dotcb = cbname;
}
/* decide which cut buffer to use */
if (!cbname)
{
/* free up the last anonymous cut buffer */
cutfree(&anon[NANONS - 1]);
/* shift the anonymous cut buffers */
for (i = NANONS - 1; i > 0; i--)
{
anon[i] = anon[i - 1];
}
/* use the first anonymous cut buffer */
cb = anon;
cb->nblks = 0;
}
else if (cbname >= 'a' && cbname <= 'z')
{
cb = &named[cbname - 'a'];
cutfree(cb);
}
#ifndef CRUNCH
else if (cbname >= 'A' && cbname <= 'Z')
{
cb = &named[cbname - 'A'];
if (cb->nblks > 0)
{
/* resolve linemode/charmode differences */
if (!lnmode && cb->lnmode)
{
from &= ~(BLKSIZE - 1);
if (markidx(to) != 0 || to == from)
{
to = to + BLKSIZE - markidx(to);
}
lnmode = TRUE;
}
/* insert the old cut-buffer before the new text */
mark[28] = to;
delthru = paste(from, FALSE, TRUE);
if (delthru == MARK_UNSET)
{
return;
}
delthru++;
to = mark[28];
}
cutfree(cb);
}
#endif /* not CRUNCH */
else if (cbname == '.')
{
cb = &named[26];
cutfree(cb);
}
else
{
msg("Invalid cut buffer name: \"%c", cbname);
dotcb = cbname = '\0';
return;
}
cbname = '\0';
cb->tmpnum = tmpnum;
/* detect whether we're doing a line mode cut */
cb->lnmode = lnmode;
/* ---------- */
/* Reporting... */
if (markidx(from) == 0 && markidx(to) == 0)
{
rptlines = markline(to) - markline(from);
rptlabel = "yanked";
}
/* ---------- */
/* make sure each block has a physical disk address */
blksync();
/* find the first block in the cut */
line = markline(from);
for (first = 1; line > lnum[first]; first++)
{
}
/* fetch text of the block containing that line */
blkc = scan = blkget(first)->c;
/* find the mark in the block */
for (l = lnum[first - 1]; ++l < line; )
{
while (*scan++ != '\n')
{
}
}
scan += markidx(from);
/* remember the offset of the start */
cb->start = scan - blkc;
/* ---------- */
/* find the last block in the cut */
line = markline(to);
for (last = first; line > lnum[last]; last++)
{
}
/* fetch text of the block containing that line */
if (last != first)
{
blkc = scan = blkget(last)->c;
}
else
{
scan = blkc;
}
/* find the mark in the block */
for (l = lnum[last - 1]; ++l < line; )
{
while (*scan++ != '\n')
{
}
}
if (markline(to) <= nlines)
{
scan += markidx(to);
}
/* remember the offset of the end */
cb->end = scan - blkc;
/* ------- */
/* remember the physical block numbers of all included blocks */
cb->nblks = last - first;
if (cb->end > 0)
{
cb->nblks++;
}
#ifdef lint
cb->phys = (short *)0;
#else
cb->phys = (short *)malloc((unsigned)(cb->nblks * sizeof(short)));
#endif
for (i = 0; i < cb->nblks; i++)
{
cb->phys[i] = hdr.n[first++];
}
#ifndef CRUNCH
/* if we temporarily inserted text for appending, then delete that
* text now -- before the user sees it.
*/
if (delthru)
{
line = rptlines;
delete(from, delthru);
rptlines = line;
rptlabel = "yanked";
}
#endif /* not CRUNCH */
}
static void readcutblk(cb, blkno)
struct cutbuf *cb;
int blkno;
{
char cutfname[50];/* name of an old temp file */
int fd; /* either tmpfd or the result of open() */
#if MSDOS || TOS
int i;
#endif
/* decide which fd to use */
if (cb->tmpnum == tmpnum)
{
fd = tmpfd;
}
else
{
#if MSDOS || TOS
strcpy(cutfname, o_directory);
if ((i = strlen(cutfname)) && !strchr(":/\\", cutfname[i-1]))
cutfname[i++]=SLASH;
sprintf(cutfname+i, TMPNAME+3, getpid(), cb->tmpnum);
#else
sprintf(cutfname, TMPNAME, o_directory, getpid(), cb->tmpnum);
#endif
fd = open(cutfname, O_RDONLY);
}
/* get the block */
lseek(fd, (long)cb->phys[blkno] * (long)BLKSIZE, 0);
if (read(fd, tmpblk.c, (unsigned)BLKSIZE) != BLKSIZE)
{
msg("Error reading back from tmp file for pasting!");
}
/* close the fd, if it isn't tmpfd */
if (fd != tmpfd)
{
close(fd);
}
}
/* This function inserts text from a cut buffer, and returns the MARK where
* insertion ended. Return MARK_UNSET on errors.
*/
MARK paste(at, after, retend)
MARK at; /* where to insert the text */
int after; /* boolean: insert after mark? (rather than before) */
int retend; /* boolean: return end of text? (rather than start) */
{
REG struct cutbuf *cb;
REG int i;
/* handle the "doingdot" quirks */
if (doingdot)
{
if (!cbname)
{
if (dotcb >= '1' && dotcb < '1' + NANONS - 1)
{
dotcb++;
}
cbname = dotcb;
}
}
else if (cbname != '.')
{
dotcb = cbname;
}
/* decide which cut buffer to use */
if (cbname >= 'A' && cbname <= 'Z')
{
cb = &named[cbname - 'A'];
}
else if (cbname >= 'a' && cbname <= 'z')
{
cb = &named[cbname - 'a'];
}
else if (cbname >= '1' && cbname <= '9')
{
cb = &anon[cbname - '1'];
}
else if (cbname == '.')
{
cb = &named[26];
}
else if (!cbname)
{
cb = anon;
}
else
{
msg("Invalid cut buffer name: \"%c", cbname);
cbname = '\0';
return MARK_UNSET;
}
/* make sure it isn't empty */
if (cb->nblks == 0)
{
if (cbname)
msg("Cut buffer \"%c is empty", cbname);
else
msg("Cut buffer is empty");
cbname = '\0';
return MARK_UNSET;
}
cbname = '\0';
/* adjust the insertion MARK for "after" and line-mode cuts */
if (cb->lnmode)
{
at &= ~(BLKSIZE - 1);
if (after)
{
at += BLKSIZE;
}
}
else if (after)
{
/* careful! if markidx(at) == 0 we might be pasting into an
* empty line -- so we can't blindly increment "at".
*/
if (markidx(at) == 0)
{
pfetch(markline(at));
if (plen != 0)
{
at++;
}
}
else
{
at++;
}
}
/* put a copy of the "at" mark in the mark[] array, so it stays in
* sync with changes made via add().
*/
mark[27] = at;
/* simple one-block paste? */
if (cb->nblks == 1)
{
/* get the block */
readcutblk(cb, 0);
/* isolate the text we need within it */
if (cb->end)
{
tmpblk.c[cb->end] = '\0';
}
/* insert it */
ChangeText
{
add(at, &tmpblk.c[cb->start]);
}
}
else
{
/* multi-block paste */
ChangeText
{
i = cb->nblks - 1;
/* add text from the last block first */
if (cb->end > 0)
{
readcutblk(cb, i);
tmpblk.c[cb->end] = '\0';
add(at, tmpblk.c);
i--;
}
/* add intervening blocks */
while (i > 0)
{
readcutblk(cb, i);
add(at, tmpblk.c);
i--;
}
/* add text from the first cut block */
readcutblk(cb, 0);
add(at, &tmpblk.c[cb->start]);
}
}
/* Reporting... */
rptlines = markline(mark[27]) - markline(at);
rptlabel = "pasted";
/* return the mark at the beginning/end of inserted text */
if (retend)
{
return mark[27] - 1L;
}
return at;
}
#ifndef NO_AT
/* This function copies characters from a cut buffer into a string.
* It returns the number of characters in the cut buffer. If the cut
* buffer is too large to fit in the string (i.e. if cb2str() returns
* a number >= size) then the characters will not have been copied.
* It returns 0 if the cut buffer is empty, and -1 for invalid cut buffers.
*/
int cb2str(name, buf, size)
int name; /* the name of a cut-buffer to get: a-z only! */
char *buf; /* where to put the string */
unsigned size; /* size of buf */
{
REG struct cutbuf *cb;
REG char *src;
REG char *dest;
/* decide which cut buffer to use */
if (name >= 'a' && name <= 'z')
{
cb = &named[name - 'a'];
}
else
{
return -1;
}
/* if the buffer is empty, return 0 */
if (cb->nblks == 0)
{
return 0;
}
/* !!! if not a single-block cut, then fail */
if (cb->nblks != 1)
{
return size;
}
/* if too big, return the size now, without doing anything */
if (cb->end - cb->start >= size)
{
return cb->end - cb->start;
}
/* get the block */
readcutblk(cb, 0);
/* isolate the string within that blk */
if (cb->start == 0)
{
tmpblk.c[cb->end] = '\0';
}
else
{
for (dest = tmpblk.c, src = dest + cb->start; src < tmpblk.c + cb->end; )
{
*dest++ = *src++;
}
*dest = '\0';
}
/* copy the string into the buffer */
if (buf != tmpblk.c)
{
strcpy(buf, tmpblk.c);
}
/* return the length */
return cb->end - cb->start;
}
#endif