[src/trunk]: src/bin/sh - Add command completion (from FreeBSD)

[christos <christos%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/153325d254b5
branches:  trunk
changeset: 1022935:153325d254b5
user:      christos <christos%NetBSD.org@localhost>
date:      Sun Aug 15 10:17:55 2021 +0000

description:
- Add command completion (from FreeBSD)
- Use EL_SAFEREAD

diffstat:

 bin/sh/histedit.c   |  136 +++++++++++++++++++++++++++++++++++++++++++++++----
 bin/sh/myhistedit.h |    7 +-
 2 files changed, 127 insertions(+), 16 deletions(-)

diffs (230 lines):

diff -r c442ad58d10d -r 153325d254b5 bin/sh/histedit.c
--- a/bin/sh/histedit.c Sun Aug 15 10:12:54 2021 +0000
+++ b/bin/sh/histedit.c Sun Aug 15 10:17:55 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: histedit.c,v 1.55 2019/02/10 19:21:52 kre Exp $        */
+/*     $NetBSD: histedit.c,v 1.56 2021/08/15 10:17:55 christos Exp $   */
 
 /*-
  * Copyright (c) 1993
@@ -37,11 +37,13 @@
 #if 0
 static char sccsid[] = "@(#)histedit.c 8.2 (Berkeley) 5/4/95";
 #else
-__RCSID("$NetBSD: histedit.c,v 1.55 2019/02/10 19:21:52 kre Exp $");
+__RCSID("$NetBSD: histedit.c,v 1.56 2021/08/15 10:17:55 christos Exp $");
 #endif
 #endif /* not lint */
 
 #include <sys/param.h>
+#include <sys/stat.h>
+#include <dirent.h>
 #include <paths.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -71,13 +73,19 @@
 EditLine *el;  /* editline cookie */
 int displayhist;
 static FILE *el_in, *el_out;
-
-STATIC const char *fc_replace(const char *, char *, char *);
+static int curpos;
 
 #ifdef DEBUG
 extern FILE *tracefile;
 #endif
 
+static const char *fc_replace(const char *, char *, char *);
+static int not_fcnumber(const char *);
+static int str_to_event(const char *, int);
+static int comparator(const void *, const void *);
+static char **sh_matches(const char *, int, int);
+static unsigned char sh_complete(EditLine *, int);
+
 /*
  * Set history and editing status.  Called whenever the status may
  * have changed (figures out what to do).
@@ -136,10 +144,11 @@
 
                                set_prompt_lit(lookupvar("PSlit"));
                                el_set(el, EL_SIGNAL, 1);
+                               el_set(el, EL_SAFEREAD, 1);
                                el_set(el, EL_ALIAS_TEXT, alias_text, NULL);
                                el_set(el, EL_ADDFN, "rl-complete",
                                    "ReadLine compatible completion function",
-                                   _el_fn_complete);
+                                   sh_complete);
                        } else {
 bad:
                                out2str("sh: can't initialize editing\n");
@@ -493,7 +502,7 @@
        return 0;
 }
 
-STATIC const char *
+static const char *
 fc_replace(const char *s, char *p, char *r)
 {
        char *dest;
@@ -512,20 +521,123 @@
        STACKSTRNUL(dest);
        dest = grabstackstr(dest);
 
-       return (dest);
+       return dest;
+}
+
+
+/*
+ * Comparator function for qsort(). The use of curpos here is to skip
+ * characters that we already know to compare equal (common prefix).
+ */
+static int
+comparator(const void *a, const void *b)
+{
+       return strcmp(*(char *const *)a + curpos,
+               *(char *const *)b + curpos);
 }
 
-int
-not_fcnumber(char *s)
+/*
+ * This function is passed to libedit's fn_complete(). The library will
+ * use it instead of its standard function to find matches, which
+ * searches for files in current directory. If we're at the start of the
+ * line, we want to look for available commands from all paths in $PATH.
+ */
+static char
+**sh_matches(const char *text, int start, int end)
+{
+       char *free_path = NULL, *dirname, *path;
+       char **matches = NULL;
+       size_t i = 0, size = 16;
+
+       if (start > 0)
+               return NULL;
+       curpos = end - start;
+       if ((free_path = path = strdup(pathval())) == NULL)
+               goto out;
+       if ((matches = malloc(size * sizeof(matches[0]))) == NULL)
+               goto out;
+       while ((dirname = strsep(&path, ":")) != NULL) {
+               struct dirent *entry;
+               DIR *dir;
+               int dfd;
+
+               if ((dir = opendir(dirname)) == NULL)
+                       continue;
+               if ((dfd = dirfd(dir)) == -1)
+                       continue;
+               while ((entry = readdir(dir)) != NULL) {
+                       struct stat statb;
+
+                       if (strncmp(entry->d_name, text, curpos) != 0)
+                               continue;
+                       if (entry->d_type == DT_UNKNOWN || entry->d_type == DT_LNK) {
+                               if (fstatat(dfd, entry->d_name, &statb, 0) == -1)
+                                       continue;
+                               if (!S_ISREG(statb.st_mode))
+                                       continue;
+                       } else if (entry->d_type != DT_REG)
+                               continue;
+                       if (++i >= size - 1) {
+                               size *= 2;
+                               if (reallocarr(&matches, size,
+                                   sizeof(*matches)))
+                               {
+                                       closedir(dir);
+                                       goto out;
+                               }
+                       }
+                       matches[i] = strdup(entry->d_name);
+               }
+               closedir(dir);
+       }
+out:
+       free(free_path);
+       if (i == 0) {
+               free(matches);
+               return NULL;
+       }
+       if (i == 1) {
+               matches[0] = strdup(matches[1]);
+               matches[i + 1] = NULL;
+       } else {
+               size_t j, k;
+
+               qsort(matches + 1, i, sizeof(matches[0]), comparator);
+               for (j = 1, k = 2; k <= i; k++)
+                       if (strcmp(matches[j] + curpos, matches[k] + curpos)
+                           == 0)
+                               free(matches[k]);
+                       else
+                               matches[++j] = matches[k];
+               matches[0] = strdup(text);
+               matches[j + 1] = NULL;
+       }
+       return matches;
+}
+
+/*
+ * This is passed to el_set(el, EL_ADDFN, ...) so that it's possible to
+ * bind a key (tab by default) to execute the function.
+ */
+unsigned char
+sh_complete(EditLine *sel, int ch __unused)
+{
+       return (unsigned char)fn_complete(sel, NULL, sh_matches,
+               L" \t\n\"\\'`@$><=;|&{(", NULL, NULL, (size_t)100,
+               NULL, &((int) {0}), NULL, NULL);
+}
+
+static int
+not_fcnumber(const char *s)
 {
        if (s == NULL)
                return 0;
         if (*s == '-')
                 s++;
-       return (!is_number(s));
+       return !is_number(s);
 }
 
-int
+static int
 str_to_event(const char *str, int last)
 {
        HistEvent he;
@@ -571,7 +683,7 @@
                if (retval == -1)
                        error("history pattern not found: %s", str);
        }
-       return (he.num);
+       return he.num;
 }
 #else
 int
diff -r c442ad58d10d -r 153325d254b5 bin/sh/myhistedit.h
--- a/bin/sh/myhistedit.h       Sun Aug 15 10:12:54 2021 +0000
+++ b/bin/sh/myhistedit.h       Sun Aug 15 10:17:55 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: myhistedit.h,v 1.13 2017/06/28 13:46:06 kre Exp $      */
+/*     $NetBSD: myhistedit.h,v 1.14 2021/08/15 10:17:55 christos Exp $ */
 
 /*-
  * Copyright (c) 1993
@@ -37,12 +37,11 @@
 extern EditLine *el;
 extern int displayhist;
 
+#include <filecomplete.h>
+
 void histedit(void);
 void sethistsize(const char *);
 void setterm(const char *);
 int inputrc(int, char **);
 void set_editrc(const char *);
 void set_prompt_lit(const char *);
-int not_fcnumber(char *);
-int str_to_event(const char *, int);
-