[src/trunk]: src/usr.bin/make make(1): clean up variable names in Dir_FindFile

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

details:   https://anonhg.NetBSD.org/src/rev/0e2f20b1e0fe
branches:  trunk
changeset: 957504:0e2f20b1e0fe
user:      rillig <rillig%NetBSD.org@localhost>
date:      Mon Nov 30 20:25:37 2020 +0000

description:
make(1): clean up variable names in Dir_FindFile

The special path entry is called .DOTLAST, therefore the local variable
should have the same name.

A variable named 'base' must not point to the slash of a pathname.  It
may only point to the character after the slash, everything else is
confusing, even if it's only for a brief moment.

diffstat:

 usr.bin/make/dir.c |  42 ++++++++++++++++--------------------------
 1 files changed, 16 insertions(+), 26 deletions(-)

diffs (129 lines):

diff -r 6ac3818ccd71 -r 0e2f20b1e0fe usr.bin/make/dir.c
--- a/usr.bin/make/dir.c        Mon Nov 30 20:17:00 2020 +0000
+++ b/usr.bin/make/dir.c        Mon Nov 30 20:25:37 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: dir.c,v 1.244 2020/11/30 20:17:00 rillig Exp $ */
+/*     $NetBSD: dir.c,v 1.245 2020/11/30 20:25:37 rillig Exp $ */
 
 /*
  * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
@@ -136,7 +136,7 @@
 #include "job.h"
 
 /*     "@(#)dir.c      8.2 (Berkeley) 1/2/94"  */
-MAKE_RCSID("$NetBSD: dir.c,v 1.244 2020/11/30 20:17:00 rillig Exp $");
+MAKE_RCSID("$NetBSD: dir.c,v 1.245 2020/11/30 20:25:37 rillig Exp $");
 
 #define DIR_DEBUG0(text) DEBUG0(DIR, text)
 #define DIR_DEBUG1(fmt, arg1) DEBUG1(DIR, fmt, arg1)
@@ -1059,24 +1059,14 @@
 Dir_FindFile(const char *name, SearchPath *path)
 {
        char *file;             /* the current filename to check */
-       const char *base;       /* Terminal name of file */
-       Boolean hasLastDot = FALSE; /* true if we should search dot last */
-       Boolean hasSlash;       /* true if 'name' contains a / */
+       const char *lastSlash;  /* the last slash in name */
+       const char *base;       /* basename(name) */
+       Boolean seenDotLast = FALSE; /* true if we should search dot last */
        struct cached_stat cst; /* Buffer for stat, if necessary */
        const char *trailing_dot = ".";
 
-       /*
-        * Find the final component of the name and note whether it has a
-        * slash in it (the name, I mean)
-        */
-       base = strrchr(name, '/'); /* XXX: confusing variable name */
-       if (base != NULL) {
-               hasSlash = TRUE;
-               base++;
-       } else {
-               hasSlash = FALSE;
-               base = name;
-       }
+       lastSlash = strrchr(name, '/');
+       base = lastSlash != NULL ? lastSlash + 1 : name;
 
        DIR_DEBUG1("Searching for %s ...", name);
 
@@ -1089,7 +1079,7 @@
        if (path->first != NULL) {
                CachedDir *dir = path->first->datum;
                if (dir == dotLast) {
-                       hasLastDot = TRUE;
+                       seenDotLast = TRUE;
                        DIR_DEBUG0("[dot last]...");
                }
        }
@@ -1100,7 +1090,7 @@
         * directory component is exactly `./', consult the cached contents
         * of each of the directories on the search path.
         */
-       if (!hasSlash || (base - name == 2 && *name == '.')) {
+       if (lastSlash == NULL || (base - name == 2 && *name == '.')) {
                SearchPathNode *ln;
 
                /*
@@ -1117,7 +1107,7 @@
                 * This is so there are no conflicts between what the user
                 * specifies (fish.c) and what pmake finds (./fish.c).
                 */
-               if (!hasLastDot && (file = DirFindDot(name, base)) != NULL)
+               if (!seenDotLast && (file = DirFindDot(name, base)) != NULL)
                        return file;
 
                for (ln = path->first; ln != NULL; ln = ln->next) {
@@ -1128,7 +1118,7 @@
                                return file;
                }
 
-               if (hasLastDot && (file = DirFindDot(name, base)) != NULL)
+               if (seenDotLast && (file = DirFindDot(name, base)) != NULL)
                        return file;
        }
 
@@ -1146,7 +1136,7 @@
         * end).]
         * This phase is only performed if the file is *not* absolute.
         */
-       if (!hasSlash) {
+       if (lastSlash == NULL) {
                DIR_DEBUG0("   failed.\n");
                misses++;
                return NULL;
@@ -1163,7 +1153,7 @@
 
                DIR_DEBUG0("   Trying subdirectories...\n");
 
-               if (!hasLastDot) {
+               if (!seenDotLast) {
                        if (dot != NULL) {
                                checkedDot = TRUE;
                                if ((file = DirLookupSubdir(dot, name)) != NULL)
@@ -1186,7 +1176,7 @@
                                return file;
                }
 
-               if (hasLastDot) {
+               if (seenDotLast) {
                        if (dot && !checkedDot) {
                                checkedDot = TRUE;
                                if ((file = DirLookupSubdir(dot, name)) != NULL)
@@ -1220,7 +1210,7 @@
                 */
                DIR_DEBUG0("   Trying exact path matches...\n");
 
-               if (!hasLastDot && cur &&
+               if (!seenDotLast && cur &&
                    ((file = DirLookupAbs(cur, name, base)) != NULL)) {
                        if (file[0] == '\0') {
                                free(file);
@@ -1242,7 +1232,7 @@
                        }
                }
 
-               if (hasLastDot && cur &&
+               if (seenDotLast && cur &&
                    ((file = DirLookupAbs(cur, name, base)) != NULL)) {
                        if (file[0] == '\0') {
                                free(file);