[src/trunk]: src/usr.bin/make make: fix types for modifier ':O' (since today)

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

details:   https://anonhg.NetBSD.org/src/rev/4a6fb7f8bd73
branches:  trunk
changeset: 1026757:4a6fb7f8bd73
user:      rillig <rillig%NetBSD.org@localhost>
date:      Sun Dec 05 17:00:02 2021 +0000

description:
make: fix types for modifier ':O' (since today)

In var.c 1.962 from 2021-12-05, the type of the array to be sorted
changed from 'const char *' to 'Substring'.  The code still worked since
the first member of Substring is 'const char *start', but that was pure
luck.

Fix the type assumptions in the comparison functions.

Add an assertion that the words must be null-terminated since the
comparison functions currently assume this.

This kind of inconsistency may be possible to detect using static
analysis, but NetBSD's lint is currently too limited for that.  To
detect this, it would have to analyze each possible comparison function
and remember the assumed type.  This type could then be compared to the
argument type of a function call to qsort or bsearch.

No functional change.

diffstat:

 usr.bin/make/var.c |  51 +++++++++++++++++++++++++++++++--------------------
 1 files changed, 31 insertions(+), 20 deletions(-)

diffs (139 lines):

diff -r b1a7ccc3f61f -r 4a6fb7f8bd73 usr.bin/make/var.c
--- a/usr.bin/make/var.c        Sun Dec 05 16:16:58 2021 +0000
+++ b/usr.bin/make/var.c        Sun Dec 05 17:00:02 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: var.c,v 1.963 2021/12/05 15:20:13 rillig Exp $ */
+/*     $NetBSD: var.c,v 1.964 2021/12/05 17:00:02 rillig Exp $ */
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1993
@@ -140,7 +140,7 @@
 #include "metachar.h"
 
 /*     "@(#)var.c      8.3 (Berkeley) 3/19/94" */
-MAKE_RCSID("$NetBSD: var.c,v 1.963 2021/12/05 15:20:13 rillig Exp $");
+MAKE_RCSID("$NetBSD: var.c,v 1.964 2021/12/05 17:00:02 rillig Exp $");
 
 /*
  * Variables are defined using one of the VAR=value assignments.  Their
@@ -3285,13 +3285,13 @@
 #endif
 
 static NUM_TYPE
-num_val(const char *s)
+num_val(Substring s)
 {
        NUM_TYPE val;
        char *ep;
 
-       val = strtoll(s, &ep, 0);
-       if (ep != s) {
+       val = strtoll(s.start, &ep, 0);
+       if (ep != s.start) {
                switch (*ep) {
                case 'K':
                case 'k':
@@ -3311,31 +3311,32 @@
 }
 
 static int
-num_cmp_asc(const void *sa, const void *sb)
+SubNumAsc(const void *sa, const void *sb)
 {
        NUM_TYPE a, b;
 
-       a = num_val(*(const char *const *)sa);
-       b = num_val(*(const char *const *)sb);
+       a = num_val(*((const Substring *)sa));
+       b = num_val(*((const Substring *)sb));
        return (a > b) ? 1 : (b > a) ? -1 : 0;
 }
 
 static int
-num_cmp_desc(const void *sa, const void *sb)
+SubNumDesc(const void *sa, const void *sb)
 {
-       return num_cmp_asc(sb, sa);
+       return SubNumAsc(sb, sa);
 }
 
 static int
-str_cmp_asc(const void *a, const void *b)
+SubStrAsc(const void *sa, const void *sb)
 {
-       return strcmp(*(const char *const *)a, *(const char *const *)b);
+       return strcmp(
+           ((const Substring *)sa)->start, ((const Substring *)sb)->start);
 }
 
 static int
-str_cmp_desc(const void *a, const void *b)
+SubStrDesc(const void *sa, const void *sb)
 {
-       return str_cmp_asc(b, a);
+       return SubStrAsc(sb, sa);
 }
 
 static void
@@ -3366,13 +3367,13 @@
        int (*cmp)(const void *, const void *);
 
        if (IsDelimiter(mod[1], ch) || mod[1] == '\0') {
-               cmp = str_cmp_asc;
+               cmp = SubStrAsc;
                (*pp)++;
        } else if (IsDelimiter(mod[2], ch) || mod[2] == '\0') {
                if (mod[1] == 'n')
-                       cmp = num_cmp_asc;
+                       cmp = SubNumAsc;
                else if (mod[1] == 'r')
-                       cmp = str_cmp_desc;
+                       cmp = SubStrDesc;
                else if (mod[1] == 'x')
                        cmp = NULL;
                else
@@ -3381,7 +3382,7 @@
        } else if (IsDelimiter(mod[3], ch) || mod[3] == '\0') {
                if ((mod[1] == 'n' && mod[2] == 'r') ||
                    (mod[1] == 'r' && mod[2] == 'n'))
-                       cmp = num_cmp_desc;
+                       cmp = SubNumDesc;
                else
                        goto bad;
                *pp += 3;
@@ -3395,8 +3396,10 @@
        words = Substring_Words(ch->expr->value.str, false);
        if (cmp == NULL)
                ShuffleSubstrings(words.words, words.len);
-       else
+       else {
+               assert(words.words[0].end[0] == '\0');
                qsort(words.words, words.len, sizeof(words.words[0]), cmp);
+       }
        Expr_SetValueOwn(ch->expr, SubstringWords_JoinFree(words));
 
        return AMR_OK;
@@ -4803,6 +4806,14 @@
        HashTable_DebugStats(&SCOPE_GLOBAL->vars, "Global variables");
 }
 
+static int
+StrAsc(const void *sa, const void *sb)
+{
+       return strcmp(
+           *((const char *const *)sa), *((const char *const *)sb));
+}
+
+
 /* Print all variables in a scope, sorted by name. */
 void
 Var_Dump(GNode *scope)
@@ -4819,7 +4830,7 @@
                *(const char **)Vector_Push(&vec) = hi.entry->key;
        varnames = vec.items;
 
-       qsort(varnames, vec.len, sizeof varnames[0], str_cmp_asc);
+       qsort(varnames, vec.len, sizeof varnames[0], StrAsc);
 
        for (i = 0; i < vec.len; i++) {
                const char *varname = varnames[i];