[src/trunk]: src/usr.bin/make make(1): clean up code for handling .for loops

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

details:   https://anonhg.NetBSD.org/src/rev/32789935e852
branches:  trunk
changeset: 977490:32789935e852
user:      rillig <rillig%NetBSD.org@localhost>
date:      Sun Oct 25 12:01:33 2020 +0000

description:
make(1): clean up code for handling .for loops

diffstat:

 usr.bin/make/for.c |  47 +++++++++++++++++++++++------------------------
 1 files changed, 23 insertions(+), 24 deletions(-)

diffs (110 lines):

diff -r f7e966e9ad0e -r 32789935e852 usr.bin/make/for.c
--- a/usr.bin/make/for.c        Sun Oct 25 10:07:23 2020 +0000
+++ b/usr.bin/make/for.c        Sun Oct 25 12:01:33 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: for.c,v 1.94 2020/10/18 17:19:54 rillig Exp $  */
+/*     $NetBSD: for.c,v 1.95 2020/10/25 12:01:33 rillig Exp $  */
 
 /*
  * Copyright (c) 1992, The Regents of the University of California.
@@ -61,7 +61,7 @@
 #include    "strlist.h"
 
 /*     "@(#)for.c      8.1 (Berkeley) 6/6/93"  */
-MAKE_RCSID("$NetBSD: for.c,v 1.94 2020/10/18 17:19:54 rillig Exp $");
+MAKE_RCSID("$NetBSD: for.c,v 1.95 2020/10/25 12:01:33 rillig Exp $");
 
 typedef enum ForEscapes {
     FOR_SUB_ESCAPE_CHAR = 0x0001,
@@ -235,13 +235,13 @@
     Words_Free(words);
 
     {
-       size_t len, n;
+       size_t nitems, nvars;
 
-       if ((len = strlist_num(&new_for->items)) > 0 &&
-           len % (n = strlist_num(&new_for->vars))) {
+       if ((nitems = strlist_num(&new_for->items)) > 0 &&
+           nitems% (nvars = strlist_num(&new_for->vars))) {
            Parse_Error(PARSE_FATAL,
                        "Wrong number of words (%zu) in .for substitution list"
-                       " with %zu vars", len, n);
+                       " with %zu vars", nitems, nvars);
            /*
             * Return 'success' so that the body of the .for loop is
             * accumulated.
@@ -334,7 +334,7 @@
 
     /* Escape ':', '$', '\\' and 'ech' - these will be removed later by
      * :U processing, see ApplyModifier_Defined. */
-    while ((ch = *item++) != 0) {
+    while ((ch = *item++) != '\0') {
        if (ch == '$') {
            size_t len = for_var_len(item);
            if (len != 0) {
@@ -349,16 +349,25 @@
     }
 }
 
+/*
+ * Scan the for loop body and replace references to the loop variables
+ * with variable references that expand to the required text.
+ *
+ * Using variable expansions ensures that the .for loop can't generate
+ * syntax, and that the later parsing will still see a variable.
+ * We assume that the null variable will never be defined.
+ *
+ * The detection of substitutions of the loop control variable is naive.
+ * Many of the modifiers use \ to escape $ (not $) so it is possible
+ * to contrive a makefile where an unwanted substitution happens.
+ */
 static char *
 ForIterate(void *v_arg, size_t *ret_len)
 {
     For *arg = v_arg;
-    unsigned int i;
-    char *var;
     const char *cp;
     const char *cmd_cp;
     const char *body_end;
-    char ch;
     Buffer cmds;
     char *cmds_str;
     size_t cmd_len;
@@ -372,23 +381,13 @@
     free(arg->parse_buf);
     arg->parse_buf = NULL;
 
-    /*
-     * Scan the for loop body and replace references to the loop variables
-     * with variable references that expand to the required text.
-     * Using variable expansions ensures that the .for loop can't generate
-     * syntax, and that the later parsing will still see a variable.
-     * We assume that the null variable will never be defined.
-     *
-     * The detection of substitutions of the loop control variable is naive.
-     * Many of the modifiers use \ to escape $ (not $) so it is possible
-     * to contrive a makefile where an unwanted substitution happens.
-     */
-
     cmd_cp = Buf_GetAll(&arg->buf, &cmd_len);
     body_end = cmd_cp + cmd_len;
     Buf_Init(&cmds, cmd_len + 256);
     for (cp = cmd_cp; (cp = strchr(cp, '$')) != NULL;) {
-       char ech;
+       char *var;
+       char ch, ech;
+       unsigned int i;
        ch = *++cp;
        if ((ch == '(' && (ech = ')', 1)) || (ch == '{' && (ech = '}', 1))) {
            cp++;
@@ -409,7 +408,7 @@
            }
            continue;
        }
-       if (ch == 0)
+       if (ch == '\0')
            break;
        /* Probably a single character name, ignore $$ and stupid ones. {*/
        if (!arg->short_var || strchr("}):$", ch) != NULL) {