michael@garfield.UUCP (Mike Rendell) (02/11/88)
Comp.sources.misc: Volume 2, Issue 55
Submitted-By: "Mike Rendell" <michael@garfield.UUCP>
Archive-Name: vi-tag-stack
[I held on to this while trying to post to comp.bugs.4bsd on r$'s suggestion.
Alas, ncoast never heard of it and our news admin isn't interested. ++bsa]
After using vi on the sun, which has a tag stack, I decided to hack it into
our vaxen's vi (4.3bsd). The following are the resulting patches for
ex_tagio.c, ex_vmain.c, ex_cmds.c and ex_cmdsub.c.
For those of you who don't have suns and don't know what I'm talking about
[and probably most of you with suns, as this feature seems to be
undocumented] this is what the tag stack does: When you tag something, your
current file (and your current position) are saved on a stack. When you
want to get back to the previous file(s) you hit ^T. This is similar to
^^ except that you can go back multiple levels. Also I have added a ":push"
command that acts like ":next" except that it pushes the current file on the
tag stack. ":pop" is the same as ^T (really visa versa, for those who know
how vi does these things...). By the way, ^T can take a count to indicate
how many levels to pop.
This feature is invaluable when poking around large programs with many
source files.
Mike Rendell
cdnnet: michael@garfield.mun.cdn
uucp: michael@garfield
{uunet,utai}!garfield!michael
Index: ex_tagio.c
*** /tmp/,RCSt1014586 Thu Nov 5 17:45:30 1987
--- /tmp/,RCSt2014586 Thu Nov 5 17:45:34 1987
***************
*** 14,19 ****
--- 14,23 ----
#include <sys/file.h>
#include "ex.h"
+ #ifdef TAGSTACK
+ #include "ex_temp.h"
+ #include "ex_vis.h"
+ #endif /* TAGSTACK */
static long offset = -1;
static long block = -1;
***************
*** 102,105 ****
--- 106,242 ----
block = -1;
bcnt = 0;
}
+ # ifdef TAGSTACK
+
+ #define TSTACKMEMSIZE (10*1024) /* 10k should suffice */
+
+ typedef struct tstack_str Tstack;
+ struct tstack_str {
+ char *t_file;
+ line t_dot;
+ int t_cursor;
+ Tstack *t_prev;
+ };
+
+ int tstack_cnt = 1;
+ static char tstack_mem[TSTACKMEMSIZE];
+ static char *tstack_ptr = tstack_mem;
+ static Tstack *tstack = (Tstack *) 0;
+
+ /*
+ * save current file/lineno/cursor
+ */
+ tag_push(fname)
+ char *fname;
+ {
+ int len;
+ Tstack *tp;
+
+ /* Don't bother if there is no current file */
+ if (fname[0] == '\0')
+ return;
+
+ /* See how much space we will need */
+ len = sizeof(Tstack) + strlen(fname) + 1;
+ /* keep things word aligned */
+ len += len & 3;
+ if (tstack_ptr + len >= &tstack_mem[TSTACKMEMSIZE]) {
+ lprintf("[Tag stack full] ");
+ return;
+ }
+ tp = (Tstack *) tstack_ptr;
+ tp->t_prev = tstack;
+ tp->t_file = tstack_ptr + sizeof(Tstack);
+ (void) strcpy(tp->t_file, fname);
+ tp->t_dot = lineDOT();
+ tp->t_cursor = inopen ? cursor - linebuf : 0;
+ tstack_ptr += len;
+ tstack = tp;
+ }
+
+ tag_pop(bang)
+ int bang;
+ {
+ Tstack *tp;
+ line *addr;
+ bool samef = 1;
+ int i;
+
+ /* Do this first so tstack_cnt will be reset regardless */
+ i = tstack_cnt;
+ tstack_cnt = 1;
+
+ if (!tstack)
+ error("Tag stack empty");
+
+ for (tp = tstack ; --i > 0 && tp ; tp = tp->t_prev)
+ ;
+ if (!tp)
+ error("Tag stack not that deep");
+
+ if (strcmp(tp->t_file, savedfile) || !edited) {
+ char cmdbuf2[sizeof(savedfile) + 10];
+ char *oglobp;
+ int omagic;
+ char opeek;
+
+ if (!bang) {
+ ckaw();
+ if (chng && dol > zero)
+ error("No write@since last change (:pop! overrides)");
+ }
+ omagic = value(MAGIC);
+ oglobp = globp;
+ strcpy(cmdbuf2, "e! ");
+ strcat(cmdbuf2, tp->t_file);
+ globp = cmdbuf2;
+ opeek = peekc; ungetchar(0);
+ commands(1, 1);
+ peekc = opeek;
+ globp = oglobp;
+ value(MAGIC) = omagic;
+ samef = 0;
+ }
+ /*
+ * Update these now that we know everything is ok
+ */
+ tstack = tp->t_prev;
+ tstack_ptr = (char *) tp;
+
+ /*
+ * Try to find the line that we were on
+ */
+ addr = zero + tp->t_dot;
+
+ /*
+ * Line is gone?
+ */
+ if (addr <= zero || addr > dol)
+ addr = one;
+ /*
+ * Try to find position on the line
+ */
+ if (inopen) {
+ char *s;
+
+ if (samef && addr != dot)
+ markDOT();
+ getline(*addr);
+ s = linebuf + (inopen ? tp->t_cursor : 0);
+ if (s >= linebuf && s < strend(linebuf)) {
+ char tbuf[8]; /* 001024 (max line) + ' ' + \0 */
+
+ if (s != linebuf)
+ (void) sprintf(tbuf, "00%d ", s - linebuf);
+ else
+ tbuf[0] = '0', tbuf[1] = '0', tbuf[2] = '\0';
+ macpush(tbuf, 0);
+ }
+ }
+ dot = addr;
+ if (ospeed > B300)
+ hold |= HOLDWIG;
+ return;
+ }
+ # endif TAGSTACK
#endif
Index: ex_cmds.c
*** /tmp/,RCSt1014564 Thu Nov 5 17:45:06 1987
--- /tmp/,RCSt2014564 Thu Nov 5 17:45:19 1987
***************
*** 410,418 ****
case 'P':
switch (peekchar()) {
- /* put */
case 'u':
tail("put");
setdot();
c = cmdreg();
eol();
--- 410,439 ----
case 'P':
switch (peekchar()) {
case 'u':
+ #ifdef TAGSTACK
+ /* push */
+ ignchar();
+ if (peekchar() == 's') {
+ tail2of("push");
+ setnoaddr();
+ ckaw();
+ ignore(quickly());
+ if (getargs())
+ makargs();
+ next();
+ tag_push(altfile);
+ c = 'e';
+ filename(c);
+ goto doecmd;
+
+ }
+ /* put */
+ tail2of("put");
+ #else /* TAGSTACK */
+ /* put */
tail("put");
+ #endif /* TAGSTACK */
setdot();
c = cmdreg();
eol();
***************
*** 437,442 ****
--- 458,482 ----
tail2of("print");
break;
+ #ifdef TAGSTACK
+ case 'o':
+ /* pop */
+ {
+ int bang;
+
+ tail("pop");
+ setnoaddr();
+ bang = exclam();
+ eol();
+ tag_pop(bang);
+ if (!inopen)
+ lchng = chng - 1;
+ else
+ nochng();
+ continue;
+ }
+ #endif TAGSTACK
+
default:
tail("print");
break;
Index: ex_cmdsub.c
*** /tmp/,RCSt1014573 Thu Nov 5 17:45:40 1987
--- /tmp/,RCSt2014573 Thu Nov 5 17:45:54 1987
***************
*** 623,628 ****
--- 623,631 ----
}
}
strcpy(cmdbuf, cp);
+ #ifdef TAGSTACK
+ tag_push(savedfile);
+ #endif /* TAGSTACK */
if (strcmp(filebuf, savedfile) || !edited) {
char cmdbuf2[sizeof filebuf + 10];
Index: ex_vmain.c
*** /tmp/,RCSt1014581 Thu Nov 5 17:45:46 1987
--- /tmp/,RCSt2014581 Thu Nov 5 17:46:02 1987
***************
*** 844,850 ****
--- 844,866 ----
globp = "e #";
goto gogo;
+ #ifdef TAGSTACK
/*
+ * Pop a tag off the stack
+ */
+ case CTRL(t):
+ if (hadcnt) {
+ extern int tstack_cnt;
+
+ tstack_cnt = cnt;
+ }
+ vsave();
+ oglobp = globp;
+ globp = "pop";
+ goto gogo;
+ #endif /* TAGSTACK */
+
+ /*
* ^] Takes word after cursor as tag, and then does
* tag command. Read ``go right to''.
*/