tcjones@watdragon.UUCP (Crocodile Dundee) (10/13/87)
here is a little thing i use all the time to get into vi without having
to type a filename terribly often. all in the name of fewer keystrokes.
try it.
- terry.
# This is a shell archive. Remove anything before this line,
# then unpack it by saving it in a file and typing "sh file".
# Contents: README Makefile MANIFEST edoc e.c
echo x - README
sed 's/^@//' > "README" <<'@//E*O*F README//'
basically e is a little thingamy to let you get into vi with more ease.
i find it useful - even given a shell with history. it keeps a short history
of the files that have been vi'ed most recently in each directory. thus it is
nice to be able to do
cd somewhere
e
and get straight into the file you were last working on in the directory
somewhere.
there is some documentation and examples in the file edoc.
before compiling you should change the
#define VI "/usr/ucb/vi"
line in e.c if your vi is located elsewhere.
and the DEST line in Makefile.
this will run just fine on 4.[23] but i suspect other versions will have
a little trouble. the readdir/opendir stuff of BSD is used for spelling
corrections and can be easily rewritten for nonBSD - or you can simply comment
out the last two functions of e.c [spell_help() and sp_dist()] and all
references to them at the cost of faster but maybe a less helpful program.
this appears free of major bugs (famous last words) - i'd really like to hear
about anything that goes wrong &/| fixes/enhancements. comments on what is
wrong and how it could be better/faster are also welcome...
terry jones
----------------------here's every email address i can find---------------------
USENET : {ihnp4,allegra,decvax,utzoo,utcsri}!watmath!watdragon!tcjones
UUCP : {ihnp4,decvax,utzoo}!watmath!watdragon!tcjones
CSNET : tcjones%watdragon@waterloo.csnet
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Internet: tcjones@er.waterloo.edu
Bitnet : tcjones@watdragon
CDNnet : tcjones@er.waterloo.cdn
from oz : tcjones@er.waterloo.cdn@munnari
SNAIL : Terry Jones/Department of Computer Science
MAIL /University of Waterloo/Waterloo/Ontario/Canada/N2L 3G1
PHONENET: 1 519 885-6686 (work?) or 1 519 884-6338 (home)
--------------------------------------------------------------------------------
@//E*O*F README//
chmod u=rw,g=r,o=r README
echo x - Makefile
sed 's/^@//' > "Makefile" <<'@//E*O*F Makefile//'
CC = cc
CFLAGS = -O
DEST = /u/tcjones/bin/e
SOURCE = e.c
$(DEST) : $(SOURCE)
$(DEST):
$(CC) $(CFLAGS) -o $(DEST) $(SOURCE)
strip $(DEST)
@//E*O*F Makefile//
chmod u=rw,g=rx,o=rx Makefile
echo x - MANIFEST
sed 's/^@//' > "MANIFEST" <<'@//E*O*F MANIFEST//'
edoc
e.c
Makefile
MANIFEST
@//E*O*F MANIFEST//
chmod u=rw,g=r,o=r MANIFEST
echo x - edoc
sed 's/^@//' > "edoc" <<'@//E*O*F edoc//'
e is an interface to vi that maintains a history of the most recently e'ed
files for each directory. it is used with exactly the same syntax etc as vi is.
a file called .e is kept in each directory. this contains the history and is
kept to a small length (<10 lines). spelling corrections are suggested for
simple mistakes (omitted character, interchanged characters, extra character).
the history file is rearranged with each use to place the last e'ed file at
the end of the list. duplicate entries are removed (in most situations).
a list of the command line variations is given below.
e [vi's the last file that was e'ed in this directory]
e - [prints the history for this directory and allows selection
of a previous file - or a new one]
e . [prints the history for this directory without asking for input]
e -t tag [the usual tag entry to vi]
e -r [invokes vi -r]
e -r file [invokes vi -r file]
e -pat [vi's the last file that was e'ed with the string 'pat' on
the command line]
e +cmd [vi's the last file that was e'ed in this directory but executes
'cmd' on the way into vi]
e file [vi's the file and adds it to the history list. minor spelling
corrections are suggested if 'file' does not exist but is close
(in spelling) to some file that does]
e files [vi's the files and adds them (as a single entry) to the history]
"features".
==========
when using "e -" the terminal is put into cbreak mode. if the first
character typed is a digit (in the acceptable range of history items)
then you will get the history item without further ado. thus if you
have a file called 4play and you try and "e" it from within a "e -"
then you'll probably end up it the wrong place.
also the history length must be less than or equal to 9 (the code sets
it to 8 at present (HIST_LINES)). this, i find, is enough but you may want
more. the problem with having more is that with "e -" you go into cbreak
and the first digit entered is taken to mean i want the nth last file. this
saves the need for hitting return. do what you will, but i like it this way.
with the history being kept as a most recently used list 8 file names
should be enough.
the numbering on "e -" and "e ." is slightly different. the "e -" option
is meant so that you can look at the number next to the file name and hit
it easily. with "e ." you see what files you would get if you did a "e -3" (etc)
and so it makes sense that "e -1" should give the second last file. that way you
can pop in and out of two files by repeated "e -1"'s (if you don't do ctrl-^).
once again, that's the way it is...
examples.
=========
with a ".e" file containing
fred.c [5]: fred.c
jane [4]: jane
alison "e ." will give [3]: alison
+/main pete.c [2]: +/main pete.c
bigmac [1]: bigmac
fries juice [0]: fries juice
so "e" will get you fries and then juice.
"e -" will present the above and ask for a number (RETURN=0).
"e -ali" will get you alison.
"e +/ketchup" will get you fries and juice, searching for ketchup in fries.
"e bigamc" will ask if you want to correct to bigmac. n or N
will do the correction, q or Q will quit, anything else will go ahead.
to be added?
============
allow backspacing on a select line.
uncompress and recompress .Z files automatically?
plenty of fancy things
a man page
@//E*O*F edoc//
chmod u=rw,g=rx,o=rx edoc
echo x - e.c
sed 's/^@//' > "e.c" <<'@//E*O*F e.c//'
/*
* e.c - a friendly interface to vi
*
* Terry Jones {ihnp4,allegra,decvax,utzoo,utcsri}!watmath!watdragon!tcjones
* Department of Computer Science
* University of Waterloo
* Waterloo, Ontario, Canada. N2L 3G1
*
*
* best vi'ed with ts=4 sw=4
* to compile: cc -o e -O e.c
*/
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <sys/dir.h>
#include <sys/inode.h>
#include <sgtty.h>
#include <strings.h>
#include <signal.h>
#include <ctype.h>
#define VI "/usr/ucb/vi"
#define HIST ".e"
#define HIST_LINES 8
#define HIST_CHARS 512
#define ARG_CHARS 100
#define MAX_ARGS 10
#define RUBOUT '\077'
char history[HIST_CHARS];
char arg[ARG_CHARS];
char *hist[HIST_LINES];
char temp[HIST_CHARS];
char *tmp_file="._vihistXXXXXX";
void
do_vi(thing)
char *thing;
{
/* split the arguments in 'thing' up and exec vi on them */
char *args[MAX_ARGS];
char *this,*next;
register i;
args[0]=VI;
args[1]=thing;
i=1;
while (*thing!='\0'&&(thing=index(thing,' '))!=NULL){
*thing++='\0';
if (*thing!='\0'){
args[++i]=thing;
}
}
args[++i]=NULL;
if (execvp(VI,args)==-1){
perror(VI);
exit(1);
}
}
main(c,v)
int c;
char **v;
{
char *last_file();
extern clean_up();
/* make sure we reset the terminal on our way out if we get interrupted */
if (signal(SIGINT, SIG_IGN) != SIG_IGN){
signal(SIGINT, clean_up);
}
switch (c){
case 1:
/* just go and vi the last file that was vi'ed */
last_file();
do_vi(arg);
break;
case 2:
switch ((*++v)[0]){
case '-':
if ((c=(*v)[1])=='\0'){
/* this is a select from history, ask what they want */
ask_hist();
do_vi(arg);
}
else if (isdigit(c)){
/* get the nth last file from the history and vi it */
nth_hist(c-'0');
do_vi(arg);
}
else if (c=='t'&&(*v)[2]=='\0'){
/* this is an empty tag - ignore it */
do_vi(*v);
}
else if (c=='r'&&(*v)[2]=='\0'){
/* a recover, just pass it to vi and don't interfere */
do_vi(*v);
}
else{
/* this is a pattern - try to match it */
find_match(++*v);
do_vi(arg);
}
break;
case '+':
/* a command, put it before the last file name etc */
insert_command(*v);
do_vi(arg);
break;
case '.':
/* just give a history list if there is only a dot */
if ((*v)[1]=='\0'){
register ct;
register i;
read_hist();
ct=split_hist();
for (i=0;i<ct;i++){
fprintf(stderr,"\t[%d]: %s\n",ct-i-1,hist[ct-i-1]);
}
exit(0);
}
/*
WARNING!
the switch falls through in the case where there is a
pattern that starts with a period
*/
default :
/* looks like it's just a plain old file name. vi it! */
normal(*v);
do_vi(arg);
break;
}
default:
/* a bunch of arguments, fix the history & vi them all as normal */
multiple(c,v);
do_vi(arg);
break;
}
}
read_hist()
{
/*
read the history file and break it up into lines in the global variable
'history'. do the appropriate checks to see that it exists etc...
*/
register vh;
register bytes;
register offset;
struct stat buf;
/*
if there is no history file then say so and get out of here - they
had nobusiness asking for access to the history
*/
if ((vh=open(HIST,O_RDONLY))==-1){
perror(HIST);
exit(1);
}
/* stat it */
if (fstat(vh,&buf)==-1){
perror(HIST);
exit(1);
}
/*
set 'offset' so that we can read the last portion of the history
file only. if there are less than HIST_CHARS characters in the
file then we will start reading at 0, otherwise at HIST_CHARS
characters before the end of the file.
*/
offset=(int)buf.st_size-HIST_CHARS<0 ? 0 : buf.st_size-HIST_CHARS;
/* move to that place in the file */
if (lseek(vh,(long)offset,L_SET)==-1){
perror(HIST);
exit(1);
}
/* and READ! */
if ((bytes=read(vh,history,HIST_CHARS))==-1){
perror(HIST);
exit(1);
}
/* if we didn't come up with ANYTHING we may as well leave */
if (!bytes){
fprintf(stderr,"Empty %s file.\n",HIST);
exit(1);
}
/* zap the newline (which should be there) for now */
if (history[--bytes]=='\n'){
history[bytes]='\0';
}
/* and get out of here */
return(bytes);
}
char *
last_file()
{
/*
get the last name from the 'history' array and put it into 'arg'
*/
read_hist();
if (index(history,'\n')==NULL){
if (*history=='\0'){
fprintf(stderr,"%s: badly formatted.\n",HIST);
exit(1);
}
else{
sprintf(arg,"%s",history);
}
}
else{
sprintf(arg,"%s",rindex(history,'\n')+1);
}
}
split_hist()
{
/*
set the array of pointers in 'hist' to point to the succesive names
in the 'history' array. these are delimited (presumably) by newlines
and so they're easy to catch...
what in fact is done is that the history array is copied and we set
the pointers up and set the newlines to be '\0' s. this way we don't
mess up the history array as we will want it intact later on (maybe).
*/
char *tmp;
register count;
/* copy it */
sprintf(temp,"%s",history);
/*
now run through breaking it up, setting pointers and return the number
of lines we found.
*/
for (count=0;count<HIST_LINES;count++){
if ((tmp=hist[count]=rindex(temp,'\n'))==NULL){
break;
}
*tmp='\0';
hist[count]++;
}
if (count<HIST_LINES){
hist[count++]=temp;
}
return(count);
}
nth_hist(n)
int n;
{
/*
get the nth last filename from the list. make use (of course) of
read_hist and split_hist.
*/
register count;
register i;
read_hist();
count=split_hist();
if (n>count-1){
if (count>1){
fprintf(stderr,"Only %d history items exist.\n",count);
}
else{
fprintf(stderr,"Only one history item exists.\n");
}
exit(1);
}
sprintf(arg,"%s",hist[n]);
/* rebuild the history with the selected name at the bottom */
reconstruct(n,count);
}
ask_hist()
{
/*
ask the outside world which of the files in the history is wanted.
set the terminal to cbreak.
*/
register i;
register count;
char *last;
register option;
struct sgttyb blk;
/* read and split the history file */
read_hist();
count=split_hist();
/* print the history */
for (i=0;i<count;i++){
fprintf(stderr,"\t[%d]: %s\n",count-i,hist[count-i-1]);
}
/* give them a prompt (of sorts) */
fprintf(stderr,"select -> ");
/* set the terminal up */
set_term();
/* get their response */
option=getc(stdin);
/* make the terminal 'safe' again */
unset_term();
/*
process the option and put the appropriate file name into the
arg variable.
*/
if (option=='\n'){
/* they want the last file of the list */
fprintf(stderr,"%s\n",hist[0]);
sprintf(arg,"%s",hist[0]);
return;
}
else if (option==RUBOUT){
/* they want to leave */
fprintf(stderr,"\n");
exit(1);
}
else if (option>='1'&&option<='0'+count){
/* they have requested a file by it's number */
option=option-'0';
fprintf(stderr,"%s\n",hist[option-1]);
sprintf(arg,"%s",hist[option-1]);
}
else{
/*
looks like they want to name a specific file. echo the
characters back to the screen.
*/
fprintf(stderr,"%c",option);
arg[0]=option;
i=1;
while ((arg[i]=getc(stdin))!='\n'){
i++;
}
arg[i]='\0';
option=count-1; /* a kludge for the history re-make to follow */
/* seeing as they typed in the name, try and help with spelling */
spell_help();
}
/* rebuild the history with the selected name at the bottom */
reconstruct(option-1,count);
}
FILE *
get_temp()
{
/* get ourselves a temporary file for the reconstructed history */
FILE *fp,*fopen();
mktemp(tmp_file);
if ((fp=fopen(tmp_file,"w"))==NULL){
perror(tmp_file);
exit(1);
}
return(fp);
}
close_temp(fp)
FILE *fp;
{
/* move the temporary file to be the new history */
FILE *fclose();
if (fclose(fp)==(FILE *)EOF){
fprintf(stderr,"Could not close %s\n",tmp_file);
exit(1);
}
if (rename(tmp_file,HIST)!=0){
perror("rename");
exit(1);
}
}
set_term()
{
/* go into cbreak and no echo mode */
struct sgttyb blk;
gtty(0, &blk);
blk.sg_flags |= CBREAK;
blk.sg_flags ^= ECHO;
stty(0, &blk);
}
unset_term()
{
/* get out of cbreak and no echo */
struct sgttyb blk;
gtty(0, &blk);
blk.sg_flags &= ~CBREAK;
blk.sg_flags ^= ECHO;
stty(0, &blk);
}
match(argument,pattern)
char *argument;
char *pattern;
{
/*
boneheaded but easy pattern matcher. just see if the 'pattern'
exists anywhere in the 'argument'. boyer-moore who?
*/
register length=strlen(pattern);
while (strlen(argument)>=length){
if (!strncmp(argument++,pattern,length)){
return(1);
}
}
return(0);
}
find_match(pattern)
char *pattern;
{
/*
find the name in the history list that contains the 'pattern'.
if it exists then put it into the 'arg' variable and otherwise
announce that a match couldn't be found and leave.
*/
register count;
register i;
/* read and split the history file */
read_hist();
count=split_hist();
/* try for a match with each file in turn (note that we are working
from most-recently-used backwards - probably a good thing)
*/
for (i=0;i<count;i++){
if (match(hist[i],pattern)){
sprintf(arg,"%s",hist[i]);
reconstruct(i,count);
return;
}
}
/* we couldn't match so get out of here */
fprintf(stderr,"Unable to match with \"%s\"\n",pattern);
exit(1);
}
insert_command(command)
char *command;
{
/*
they want the last file in the history but want to preceed it
this time with a command - no problems here.
*/
register count;
char *place;
/* read and split the history */
read_hist();
count=split_hist();
/*
if there was already a command there (indicated by a '+') then we
want to get rid of it. if there is a '+' but no ' ' after it then
the history file is in disarray and we will not try to recover
*/
if (*hist[0]=='+'){
if ((place=index(hist[0],' '))==NULL){
fprintf("Serious weirdenss in insert_command\n");
exit(1);
}
/* move over white space - if there is any */
while (*place==' '||*place=='\t'){
place++;
}
}
else{
/* there was no command preceeding the last file in the history */
place=hist[0];
}
/* put the new command and the filename into 'arg' */
sprintf(arg,"%s %s",command,place);
/* rebuild the history with the selected command and name at the bottom */
reconstruct(0,count);
}
reconstruct(except,count)
int except;
int count;
{
/*
reconstruct history file excepting the 'except' last.
so just copy all lines but the 'except'th last and then put in 'arg'
which contains the new line for the history
*/
register i;
FILE *tv,*get_temp();
/* get a temporary file */
tv=get_temp();
/* put in the line we still want */
for (i=count-1;i>=0;i--){
if (i!=except){
fprintf(tv,"%s\n",hist[i]);
}
}
/* put in the new line from 'arg' */
fprintf(tv,"%s\n",arg);
/* rename the temporary to be the new history file */
close_temp(tv);
}
normal(string)
char *string;
{
/*
a normal filename was found, put it into arg. first of all if there
is a history and the file is already in it (which means they could
have gotten to this file in other ways), then reconstruct the history
as though they had. also offer spelling help.
*/
register count;
register i;
/* put it into 'arg' */
sprintf(arg,"%s",string);
/* if there is a history file */
if (got_vi()){
/* read it and split it up */
read_hist();
count=split_hist();
/* if it is in the history then reconstruct and return */
for (i=0;i<count;i++){
if (!strcmp(hist[i],arg)){
reconstruct(i,count);
return;
}
}
/* it's not in the history, help with spelling then reconstruct */
spell_help();
reconstruct(HIST_LINES,count);
}
else{
/*
there is no history around so help with spelling and set up a
history for next time.
*/
spell_help();
new_vi();
}
}
multiple(number, args)
int number;
char **args;
{
/*
there were several names on the command line so we just strcat them
into the 'arg' array.
*/
register count;
register i;
*arg='\0';
while (--number){
strcat(arg,*++args);
if (number>1){
strcat(arg," ");
}
}
/*
now if there is a history file and we can find an identical line
then reconstruct with that line at the bottom.
*/
if (got_vi()){
read_hist();
count=split_hist();
for (i=0;i<count;i++){
if (!strcmp(hist[i],arg)){
reconstruct(i,count);
return;
}
}
/*
rebuild, including everything but the counth last (i.e. make
a new history by omitting the oldest file in the current one and
putting 'arg' on the end.
*/
reconstruct(HIST_LINES,count);
}
else{
/* there was no history file so try to give them one for next time */
new_vi();
}
}
got_vi()
{
/* indicate if there is a history file that they own or otherwise */
struct stat buf;
if (stat(HIST,&buf)==-1){
return(0);
}
else{
return(getuid()==buf.st_uid);
}
}
new_vi()
{
/* attempt to make a new history file - several things could go wrong */
FILE *vh,*fopen(),*fclose();
struct stat buf;
/* if you can't read the current directory, get out */
if (stat(".",&buf)==-1){
perror("stat");
exit(1);
}
/* if you own the directory (you can't normally get a history in /tmp) */
if (getuid()==buf.st_uid){
/* if we can't make a history, get out */
if ((vh=fopen(HIST,"w"))==NULL){
perror(HIST);
exit(1);
}
/* put in the 'arg' that we will be vi'ing in a second */
fprintf(vh,"%s\n",arg);
/* close the history */
if (fclose(vh)==(FILE *)EOF){
fprintf(stderr,"Could not close %s\n",VI);
exit(1);
}
/* give the history some protection - for those who want it! */
if (chmod(HIST,IREAD|IWRITE)==-1){
perror("chmod");
exit(1);
}
}
}
clean_up()
{
/* just get out after making sure things are tidy */
fprintf(stderr,"Interrupt.\n");
unlink(tmp_file);
unset_term();
exit(1);
}
spell_help()
{
/*
unashamedly stolen (and modified) from "The UNIX Programming
Environment" - Kernighan and Pike
read the directory and if the file they want (in 'arg') does not
exist then see if there is one that does that has similar spelling
to what they requested. offer the change and handle the reply.
*/
char new[ARG_CHARS];
register dist=3;
register new_dist;
DIR *dp, *opendir();
struct direct *readdir();
struct direct *entry;
register len;
struct stat buf;
/* if the file already exists just return - they don't need help */
if (stat(arg,&buf)==0){
return;
}
/* if the current directory can't be read then return */
if ((dp=opendir("."))==NULL){
return;
}
/* get the length of what we are seeking to cut down on strcmping time */
len=strlen(arg);
for (entry=readdir(dp);entry!=NULL;entry=readdir(dp)){
/* if this entry has length = sought length +/- 1 then it may be ok */
if (entry->d_ino&&entry->d_namlen>=len-1&&entry->d_namlen<=len+1){
/* get the 'distance' between what we want and this file name */
new_dist=sp_dist(entry->d_name,arg);
/* if this name is close enough and better than our current best */
if (new_dist<=dist&&new_dist!=3){
if (!new_dist){
/* if the dist is 0 then they are identical */
closedir(dp);
return;
}
/* remember the new name and distance */
strcpy(new,entry->d_name);
dist=new_dist;
}
}
}
/* close up. if we got no suitable result then simply return */
closedir(dp);
if (dist==3){
return;
}
/* offer them "new" */
set_term();
fprintf(stderr,"correct to %s [y]? ",new);
/* process the reply */
switch (getc(stdin)){
case 'N':
case 'n':
fprintf(stderr,"no\n");
break;
case 'q':
case 'Q':
fprintf(stderr,"quit\n");
unset_term();
exit(0);
break;
default :
fprintf(stderr,"yes\n");
strcpy(arg,new);
}
unset_term();
}
sp_dist(s,t)
char *s;
char *t;
{
/*
stolen from the same place as spell_help() above.
work out the distance between the strings 's' and 't' according
to the rough metric that
identical = 0
interchanged characters = 1
wrong character/extra character/missing character = 2
forget it = 3
*/
while (*s++==*t){
if (*t++=='\0'){
/* identical */
return(0);
}
}
if (*--s){
if (*t){
if (s[1]&&t[1]&&*s==t[1]&&*t==s[1]&&!strcmp(s+2,t+2)){
/* interchanged chars */
return(1);
}
if (!strcmp(s+1,t+1)){
/* wrong char */
return(2);
}
}
if (!strcmp(s+1,t)){
/* extra char in 't' */
return(2);
}
}
if (!strcmp(s,t+1)){
/* extra char in 's' */
return(2);
}
/* forget it */
return(3);
}
@//E*O*F e.c//
chmod u=rw,g=rx,o=rx e.c
echo Inspecting for damage in transit...
temp=/tmp/shar$$; dtemp=/tmp/.shar$$
trap "rm -f $temp $dtemp; exit" 0 1 2 3 15
cat > $temp <<\!!!
45 262 1867 README
10 23 141 Makefile
4 4 27 MANIFEST
84 627 3415 edoc
831 2311 16691 e.c
974 3227 22141 total
!!!
wc README Makefile MANIFEST edoc e.c | sed 's=[^ ]*/==' | diff -b $temp - >$dtemp
if [ -s $dtemp ]
then echo "Ouch [diff of wc output]:" ; cat $dtemp
else echo "No problems found."
fi
exit 0
ZZsimon@its63b.ed.ac.uk (Simon Brown) (10/24/87)
Here's a cleaned-up (I hope) version of e -
o Ported to System V.
o Puts history in the correct file even if you try to edit
files not in the current directory.
o "e -" and "e ." use the same numbering scheme.
o Multiple file-entries in history-files no longer occur.
o Uses $EDITOR instead of always using "vi".
Warning: this changed version has not been tested under BSD (cos I was
too lazy).
------------------------ cut here -------------------
#! /bin/sh
# This is a shell archive, meaning:
# 1. Remove everything above the #! /bin/sh line.
# 2. Save the resulting text in a file.
# 3. Execute the file with /bin/sh (not csh) to create:
# e.c
# This archive created: Thu Oct 15 20:17:37 1987
# By: Simon Brown (Computer Science Department, Edinburgh University)
export PATH; PATH=/bin:/usr/bin:$PATH
echo shar: "extracting 'e.c'" '(19244 characters)'
if test -f 'e.c'
then
echo shar: "will not over-write existing file 'e.c'"
else
cat << \SHAR_EOF > 'e.c'
/*
* e.c - a friendly interface to vi
*
* Terry Jones {ihnp4,allegra,decvax,utzoo,utcsri}!watmath!watdragon!tcjones
* Department of Computer Science
* University of Waterloo
* Waterloo, Ontario, Canada. N2L 3G1
*
*
* best vi'ed with ts=4 sw=4
* to compile: cc -o e -O e.c
*/
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/file.h>
#ifdef sysV
# ifdef GEC
# include <local/ndir.h>
# else
# include <ndir.h>
# endif
# include <termio.h>
# include <string.h>
# include <fcntl.h>
#else
# include <sys/dir.h>
# ifdef NFS
# include <ufs/inode.h>
# else
# include <sys/inode.h>
# endif
# include <sgtty.h>
# include <strings.h>
#endif sysV
#include <signal.h>
#include <ctype.h>
#ifdef sysV
# define VI "/usr/bin/vi"
# define index strchr
# define rindex strrchr
#else
# define VI "/usr/ucb/vi"
#endif sysV
#ifndef L_SET
# define L_SET 0
#endif
#ifndef IREAD
# define IREAD 0400
# define IWRITE 0200
#endif
#define HIST ".e"
#define HIST_LINES 8
#define HIST_CHARS 512
#define ARG_CHARS 100
#define MAX_ARGS 10
#define RUBOUT '\177'
#define HFILELEN 512
char history[HIST_CHARS];
char arg[ARG_CHARS];
char *hist[HIST_LINES];
char temp[HIST_CHARS];
char *tmp_file="._vihistXXXXXX";
char dotstring[] = ".";
char rubout = RUBOUT;
#ifdef sysV
struct termio oldblk;
#else
struct sgttyb oldblk;
#endif sysV
int term_messy = 0;
char *got_vi();
void
do_vi(thing)
char *thing;
{
/* split the arguments in 'thing' up and exec vi on them */
char *args[MAX_ARGS];
char *this,*next;
register i;
char *getenv();
if ((args[0]=getenv("EDITOR")) == 0) args[0]=VI;
args[1]=thing;
i=1;
while (*thing!='\0'&&(thing=index(thing,' '))!=NULL){
*thing++='\0';
if (*thing!='\0'){
args[++i]=thing;
}
}
args[++i]=NULL;
if (execvp(args[0],args)==-1){
perror(args[0]);
exit(1);
}
}
main(c,v)
int c;
char **v;
{
extern clean_up();
/* make sure we reset the terminal on our way out if we get interrupted */
if (signal(SIGINT, SIG_IGN) != SIG_IGN){
signal(SIGINT, clean_up);
}
switch (c){
case 1:
/* just go and vi the last file that was vi'ed */
last_file();
do_vi(arg);
break;
case 2:
switch ((*++v)[0]){
case '-':
if ((c=(*v)[1])=='\0'){
/* this is a select from history, ask what they want */
ask_hist();
do_vi(arg);
}
else if (isdigit(c)){
/* get the nth last file from the history and vi it */
nth_hist(c-'0');
do_vi(arg);
}
else if (c=='t'&&(*v)[2]=='\0'){
/* this is an empty tag - ignore it */
do_vi(*v);
}
else if (c=='r'&&(*v)[2]=='\0'){
/* a recover, just pass it to vi and don't interfere */
do_vi(*v);
}
else{
/* this is a pattern - try to match it */
find_match(++*v);
do_vi(arg);
}
break;
case '+':
/* a command, put it before the last file name etc */
insert_command(*v);
do_vi(arg);
break;
case '.':
/* just give a history list if there is only a dot */
if ((*v)[1]=='\0'){
register ct;
register i;
read_hist(dotstring);
ct=split_hist();
for (i=0;i<ct;i++){
fprintf(stderr,"\t[%d]: %s\n",ct-i-1,hist[ct-i-1]);
}
exit(0);
}
/*
WARNING!
the switch falls through in the case where there is a
pattern that starts with a period
*/
default :
/* looks like it's just a plain old file name. vi it! */
normal(*v);
do_vi(arg);
break;
}
default:
/* a bunch of arguments, fix the history & vi them all as normal */
multiple(c,v);
do_vi(arg);
break;
}
}
read_hist(dirname)
char *dirname;
{
/*
read the history file and break it up into lines in the global variable
'history'. do the appropriate checks to see that it exists etc...
*/
register vh;
register bytes;
register offset;
struct stat buf;
char dirbuffer[HFILELEN];
/*
if there is no history file then say so and get out of here - they
had nobusiness asking for access to the history
*/
sprintf(dirbuffer,"%s/%s", dirname, HIST);
if ((vh=open(dirbuffer,O_RDONLY))==-1){
perror(dirbuffer);
exit(1);
}
/* stat it */
if (fstat(vh,&buf)==-1){
perror(dirbuffer);
exit(1);
}
/*
set 'offset' so that we can read the last portion of the history
file only. if there are less than HIST_CHARS characters in the
file then we will start reading at 0, otherwise at HIST_CHARS
characters before the end of the file.
*/
offset=(int)buf.st_size-HIST_CHARS<0 ? 0 : buf.st_size-HIST_CHARS;
/* move to that place in the file */
if (lseek(vh,(long)offset,L_SET)==-1){
perror(dirbuffer);
exit(1);
}
/* and READ! */
if ((bytes=read(vh,history,HIST_CHARS))==-1){
perror(dirbuffer);
exit(1);
}
/* if we didn't come up with ANYTHING we may as well leave */
if (!bytes){
fprintf(stderr,"Empty %s file.\n",dirbuffer);
exit(1);
}
/* zap the newline (which should be there) for now */
if (history[--bytes]=='\n'){
history[bytes]='\0';
}
/* and get out of here */
return(bytes);
}
last_file()
{
/*
get the last name from the 'history' array and put it into 'arg'
*/
read_hist(dotstring);
if (index(history,'\n')==NULL){
if (*history=='\0'){
fprintf(stderr,"%s: badly formatted.\n",HIST);
exit(1);
}
else{
sprintf(arg,"%s",history);
}
}
else{
sprintf(arg,"%s",rindex(history,'\n')+1);
}
}
split_hist()
{
/*
set the array of pointers in 'hist' to point to the succesive names
in the 'history' array. these are delimited (presumably) by newlines
and so they're easy to catch...
what in fact is done is that the history array is copied and we set
the pointers up and set the newlines to be '\0' s. this way we don't
mess up the history array as we will want it intact later on (maybe).
*/
char *tmp;
register count;
/* copy it */
sprintf(temp,"%s",history);
/*
now run through breaking it up, setting pointers and return the number
of lines we found.
*/
for (count=0;count<HIST_LINES;count++){
if ((tmp=hist[count]=rindex(temp,'\n'))==NULL){
break;
}
*tmp='\0';
hist[count]++;
}
if (count<HIST_LINES){
hist[count++]=temp;
}
return(count);
}
nth_hist(n)
int n;
{
/*
get the nth last filename from the list. make use (of course) of
read_hist and split_hist.
*/
register count;
register i;
read_hist(dotstring);
count=split_hist();
if (n>count-1){
if (count>1){
fprintf(stderr,"Only %d history items exist.\n",count);
}
else{
fprintf(stderr,"Only one history item exists.\n");
}
exit(1);
}
sprintf(arg,"%s",hist[n]);
/* rebuild the history with the selected name at the bottom */
reconstruct(n,count,dotstring);
}
ask_hist()
{
/*
ask the outside world which of the files in the history is wanted.
set the terminal to cbreak.
*/
register i;
register count;
char *last;
register option;
/* read and split the history file */
read_hist(dotstring);
count=split_hist();
/* print the history */
for (i=0;i<count;i++){
fprintf(stderr,"\t[%d]: %s\n",count-(i+1),hist[count-i-1]);
}
/* give them a prompt (of sorts) */
fprintf(stderr,"select -> ");
/* set the terminal up */
set_term();
/* get their response */
option=getc(stdin);
/* make the terminal 'safe' again */
unset_term();
/*
process the option and put the appropriate file name into the
arg variable.
*/
if (option=='\n'){
/* they want the last file of the list */
fprintf(stderr,"%s\n",hist[0]);
sprintf(arg,"%s",hist[0]);
return;
}
else if (option==rubout){
/* they want to leave */
fprintf(stderr,"\n");
exit(1);
}
else if (option>='0' && option<='0'+count){
/* they have requested a file by it's number */
option=option-'0';
fprintf(stderr,"%s\n",hist[option]);
sprintf(arg,"%s",hist[option]);
}
else{
/*
looks like they want to name a specific file. echo the
characters back to the screen.
*/
fprintf(stderr,"%c",option);
arg[0]=option;
i=1;
while ((arg[i]=getc(stdin))!='\n'){
i++;
}
arg[i]='\0';
option=count-1; /* a kludge for the history re-make to follow */
/* seeing as they typed in the name, try and help with spelling */
spell_help();
}
/* rebuild the history with the selected name at the bottom */
reconstruct(option-1,count,dotstring);
}
FILE *
get_temp()
{
/* get ourselves a temporary file for the reconstructed history */
FILE *fp,*fopen();
mktemp(tmp_file);
if ((fp=fopen(tmp_file,"w"))==NULL){
perror(tmp_file);
exit(1);
}
return(fp);
}
close_temp(fp,filename)
FILE *fp;
char *filename;
{
/* move the temporary file to be the new history */
FILE *fclose();
char dirbuffer[HFILELEN];
char *fptr;
if (fclose(fp)==(FILE *)EOF){
fprintf(stderr,"Could not close %s\n",tmp_file);
exit(1);
}
strcpy(dirbuffer, filename);
if ((fptr=rindex(dirbuffer,'/'))==0){
strcpy(dirbuffer,dotstring);
fptr = &dirbuffer[1];
}
sprintf(fptr,"/%s", HIST);
if (rename(tmp_file,dirbuffer)!=0){
perror("rename");
exit(1);
}
}
set_term()
{
/* go into cbreak and no echo mode */
#ifdef sysV
struct termio blk;
ioctl(0, TCGETA, &blk);
oldblk = blk;
rubout = blk.c_cc[VERASE];
blk.c_lflag &= ~(ICANON|ECHO|ECHONL);
blk.c_cc[VMIN] = 1;
blk.c_cc[VTIME] = 0;
ioctl(0, TCSETA, &blk);
#else
struct sgttyb blk;
gtty(0, &blk);
oldblk = blk;
rubout = blk.sg_erase;
blk.sg_flags |= CBREAK;
blk.sg_flags ^= ECHO;
stty(0, &blk);
#endif sysV
term_messy = 1;
}
unset_term()
{
/* get out of cbreak and no echo */
if (term_messy) {
#ifdef sysV
ioctl(0, TCSETA, &oldblk);
#else
stty(0, &oldblk);
#endif sysV
term_messy = 0;
}
}
match(argument,pattern)
char *argument;
char *pattern;
{
/*
boneheaded but easy pattern matcher. just see if the 'pattern'
exists anywhere in the 'argument'. boyer-moore who?
*/
register length=strlen(pattern);
while (strlen(argument)>=length){
if (!strncmp(argument++,pattern,length)){
return(1);
}
}
return(0);
}
find_match(pattern)
char *pattern;
{
/*
find the name in the history list that contains the 'pattern'.
if it exists then put it into the 'arg' variable and otherwise
announce that a match couldn't be found and leave.
*/
register count;
register i;
/* read and split the history file */
read_hist(dotstring);
count=split_hist();
/* try for a match with each file in turn (note that we are working
from most-recently-used backwards - probably a good thing)
*/
for (i=0;i<count;i++){
if (match(hist[i],pattern)){
sprintf(arg,"%s",hist[i]);
reconstruct(i,count,dotstring);
return;
}
}
/* we couldn't match so get out of here */
fprintf(stderr,"Unable to match with \"%s\"\n",pattern);
exit(1);
}
insert_command(command)
char *command;
{
/*
they want the last file in the history but want to preceed it
this time with a command - no problems here.
*/
register count;
char *place;
/* read and split the history */
read_hist(dotstring);
count=split_hist();
/*
if there was already a command there (indicated by a '+') then we
want to get rid of it. if there is a '+' but no ' ' after it then
the history file is in disarray and we will not try to recover
*/
if (*hist[0]=='+'){
if ((place=index(hist[0],' '))==NULL){
fprintf("Serious weirdenss in insert_command\n");
exit(1);
}
/* move over white space - if there is any */
while (*place==' '||*place=='\t'){
place++;
}
}
else{
/* there was no command preceeding the last file in the history */
place=hist[0];
}
/* put the new command and the filename into 'arg' */
sprintf(arg,"%s %s",command,place);
/* rebuild the history with the selected command and name at the bottom */
reconstruct(0,count,dotstring);
}
reconstruct(except,count,dirname)
int except;
int count;
char *dirname;
{
/*
reconstruct history file excepting the 'except' last.
so just copy all lines but the 'except'th last and then put in 'arg'
which contains the new line for the history
*/
register i;
FILE *tv,*get_temp();
char *fptr;
/* get a temporary file */
tv=get_temp();
/* grab tail of file name. */
if (fptr=rindex(arg,'/')) fptr++;
else fptr=arg;
/* put in the line we still want - ignoring duplicates of this file */
for (i=count-1;i>=0;i--){
if (i!=except && strcmp(hist[i],fptr)!=0){
fprintf(tv,"%s\n",hist[i]);
}
}
/* put in the new line from 'arg' */
fprintf(tv,"%s\n",fptr);
/* rename the temporary to be the new history file */
close_temp(tv,arg);
}
normal(string)
char *string;
{
/*
a normal filename was found, put it into arg. first of all if there
is a history and the file is already in it (which means they could
have gotten to this file in other ways), then reconstruct the history
as though they had. also offer spelling help.
*/
register count;
register i;
char *edir;
/* put it into 'arg' */
sprintf(arg,"%s",string);
/* if there is a history file */
if (edir=got_vi(string)){
/* read it and split it up */
read_hist(edir);
count=split_hist();
/* if it is in the history then reconstruct and return */
for (i=0;i<count;i++){
if (!strcmp(hist[i],arg)){
reconstruct(i,count, edir);
return;
}
}
/* it's not in the history, help with spelling then reconstruct */
spell_help();
reconstruct(HIST_LINES,count,edir);
}
else{
/*
there is no history around so help with spelling and set up a
history for next time.
*/
spell_help();
new_vi(string);
}
}
multiple(number, args)
int number;
char **args;
{
/*
there were several names on the command line so we just strcat them
into the 'arg' array.
*/
register count;
register i;
char *edir;
*arg='\0';
while (--number){
strcat(arg,*++args);
if (number>1){
strcat(arg," ");
}
}
/*
now if there is a history file and we can find an identical line
then reconstruct with that line at the bottom.
*/
if (edir=got_vi(*--args)){
read_hist(edir);
count=split_hist();
for (i=0;i<count;i++){
if (!strcmp(hist[i],arg)){
reconstruct(i,count,edir);
return;
}
}
/*
rebuild, including everything but the counth last (i.e. make
a new history by omitting the oldest file in the current one and
putting 'arg' on the end.
*/
reconstruct(HIST_LINES,count,edir);
}
else{
/* there was no history file so try to give them one for next time */
new_vi(*args);
}
}
char *
got_vi(filename)
char *filename;
{
/* indicate if there is a history file that they own or otherwise */
struct stat buf;
static char dirbuffer[HFILELEN];
char *fptr;
strcpy(dirbuffer, filename);
if ((fptr=rindex(dirbuffer,'/'))==0) {
for (fptr=dirbuffer; *fptr; fptr++);
*fptr='/';
}
fptr++;
strcpy(fptr,HIST);
if (stat(dirbuffer,&buf)==-1 || getuid()!=buf.st_uid){
return((char *)0);
}
else{
*--fptr = '\0';
return(dirbuffer);
}
}
new_vi(filename)
{
/* attempt to make a new history file - several things could go wrong */
FILE *vh,*fopen(),*fclose();
struct stat buf;
char dirbuffer[HFILELEN];
char *fptr;
/* grab directory of filename */
strcpy(dirbuffer, filename);
if (fptr=rindex(dirbuffer,'/')) *++fptr = '\0';
else {
strcpy(dirbuffer,"./");
fptr = &dirbuffer[2];
}
/* if you can't read the current directory, get out */
if (stat(dirbuffer,buf)==-1){
perror("stat");
exit(1);
}
/* if you own the directory (you can't normally get a history in /tmp) */
if (getuid()==buf.st_uid){
/* if we can't make a history, get out */
strcat(dirbuffer,HIST);
if ((vh=fopen(dirbuffer,"w"))==NULL){
perror(dirbuffer);
exit(1);
}
/* put in the 'arg' that we will be vi'ing in a second,
after extracting it's tail. */
if (fptr=rindex(arg,'/')) fptr++;
else fptr=arg;
fprintf(vh,"%s\n",fptr);
/* close the history */
if (fclose(vh)==(FILE *)EOF){
fprintf(stderr,"Could not close %s\n",dirbuffer);
exit(1);
}
/* give the history some protection - for those who want it! */
if (chmod(dirbuffer,IREAD|IWRITE)==-1){
perror("chmod");
exit(1);
}
}
}
clean_up()
{
/* just get out after making sure things are tidy */
fprintf(stderr,"Interrupt.\n");
unlink(tmp_file);
unset_term();
exit(1);
}
spell_help()
{
/*
unashamedly stolen (and modified) from "The UNIX Programming
Environment" - Kernighan and Pike
read the directory and if the file they want (in 'arg') does not
exist then see if there is one that does that has similar spelling
to what they requested. offer the change and handle the reply.
*/
char new[ARG_CHARS];
register dist=3;
register new_dist;
DIR *dp, *opendir();
struct direct *readdir();
struct direct *entry;
register len;
struct stat buf;
char dirbuffer[HFILELEN];
char *fptr;
/* if the file already exists just return - they don't need help */
if (stat(arg,&buf)==0){
return;
}
/* if the current directory can't be read then return */
strcpy(dirbuffer, arg);
if (fptr=rindex(dirbuffer,'/')) *fptr++='\0';
else {
strcpy(dirbuffer, dotstring);
fptr=arg;
}
if ((dp=opendir(dirbuffer))==NULL){
return;
}
/* get the length of what we are seeking to cut down on strcmping time */
len=strlen(fptr);
for (entry=readdir(dp);entry!=NULL;entry=readdir(dp)){
/* if this entry has length = sought length +/- 1 then it may be ok */
if (entry->d_ino&&entry->d_namlen>=len-1&&entry->d_namlen<=len+1){
/* get the 'distance' between what we want and this file name */
new_dist=sp_dist(entry->d_name,fptr);
/* if this name is close enough and better than our current best */
if (new_dist<=dist&&new_dist!=3){
if (!new_dist){
/* if the dist is 0 then they are identical */
closedir(dp);
return;
}
/* remember the new name and distance */
strcpy(new,entry->d_name);
dist=new_dist;
}
}
}
/* close up. if we got no suitable result then simply return */
closedir(dp);
if (dist==3){
return;
}
/* offer them "new" */
set_term();
fprintf(stderr,"correct to %s [y]? ",new);
/* process the reply */
switch (getc(stdin)){
case 'N':
case 'n':
fprintf(stderr,"no\n");
break;
case 'q':
case 'Q':
fprintf(stderr,"quit\n");
unset_term();
exit(0);
break;
default :
fprintf(stderr,"yes\n");
if (fptr==arg)
strcpy(arg,new);
else sprintf(arg,"%s/%s", dirbuffer, new);
}
unset_term();
}
sp_dist(s,t)
char *s;
char *t;
{
/*
stolen from the same place as spell_help() above.
work out the distance between the strings 's' and 't' according
to the rough metric that
identical = 0
interchanged characters = 1
wrong character/extra character/missing character = 2
forget it = 3
*/
while (*s++==*t){
if (*t++=='\0'){
/* identical */
return(0);
}
}
if (*--s){
if (*t){
if (s[1]&&t[1]&&*s==t[1]&&*t==s[1]&&!strcmp(s+2,t+2)){
/* interchanged chars */
return(1);
}
if (!strcmp(s+1,t+1)){
/* wrong char */
return(2);
}
}
if (!strcmp(s+1,t)){
/* extra char in 't' */
return(2);
}
}
if (!strcmp(s,t+1)){
/* extra char in 's' */
return(2);
}
/* forget it */
return(3);
}
SHAR_EOF
chmod +x 'e.c'
fi
exit 0
# End of shell archive
--
----------------------------------
| Simon Brown | UUCP: seismo!mcvax!ukc!{lfcs,its63b}!simon
| Department of Computer Science | JANET: simon@uk.ac.ed.{lfcs,its63b}
| University of Edinburgh, | ARPA: simon%lfcs.ed.ac.uk@cs.ucl.ac.uk
| Scotland, UK. | or simon%its63b.ed.ac.uk@cs.ucl.ac.uk
---------------------------------- or simon%cstvax.ed.ac.uk@cs.ucl.ac.uk
"Life's like that, you know"