[hackers] [libgrapheme] Avoid undefined behaviour and memory leaks in case-data-generator || Laslo Hunhold

[git]

commit 4182a14424c1e27b943187e230948ee31d6d66ba
Author:     Laslo Hunhold <d...@frign.de>
AuthorDate: Sat Oct 8 13:14:48 2022 +0200
Commit:     Laslo Hunhold <d...@frign.de>
CommitDate: Sat Oct 8 13:14:48 2022 +0200

    Avoid undefined behaviour and memory leaks in case-data-generator
    
    This was found using the clang-sanitizers and was pretty tough to spot.
    
    The first part does not influence program-operation as is, but checking
    first if tmp2 is NULL avoids undefined behaviour of adding a non-zero
    offset to NULL.
    
    Signed-off-by: Laslo Hunhold <d...@frign.de>

diff --git a/gen/case.c b/gen/case.c
index f953fdc..174a8bd 100644
--- a/gen/case.c
+++ b/gen/case.c
@@ -119,11 +119,14 @@ parse_cp_list(const char *str, uint_least32_t **cp, 
size_t *cplen)
        }
 
        /* go through the string again, parsing the numbers */
-       for (i = 0, tmp1 = tmp2 = str; tmp2 != NULL; i++, tmp1 = tmp2 + 1) {
+       for (i = 0, tmp1 = tmp2 = str; tmp2 != NULL; i++) {
                tmp2 = strchr(tmp1, ' ');
                if (hextocp(tmp1, tmp2 ? (size_t)(tmp2 - tmp1) : strlen(tmp1), 
&((*cp)[i]))) {
                        return 1;
                }
+               if (tmp2 != NULL) {
+                       tmp1 = tmp2 + 1;
+               }
        }
 
        return 0;
@@ -298,5 +301,18 @@ main(int argc, char *argv[])
        }
        printf("};\n\n");
 
+       free(comp_lower.data);
+       free(comp_lower.offset);
+       free(comp_title.data);
+       free(comp_title.offset);
+       free(comp_upper.data);
+       free(comp_upper.offset);
+       free(mm_lower.major);
+       free(mm_lower.minor);
+       free(mm_title.major);
+       free(mm_title.minor);
+       free(mm_upper.major);
+       free(mm_upper.minor);
+
        return 0;
 }