add() first parameter (s2) is now const

[mmh] / sbr / utils.c

diff --git a/sbr/utils.c b/sbr/utils.c
index f964e7e..ef0ee97 100644 (file)
--- a/sbr/utils.c
+++ b/sbr/utils.c
@@ -31,7 +31,7 @@ mh_xrealloc(void *ptr, size_t size)
 
        /* Some non-POSIX realloc()s don't cope with realloc(NULL,sz) */
        if (!ptr) {
-               return mh_xcalloc((size_t) 1, size);
+               return mh_xcalloc(1, size);
        }
        if (size == 0) {
                adios(EX_SOFTWARE, NULL, "Tried to realloc 0 bytes");
@@ -65,6 +65,18 @@ mh_xcalloc(size_t nmemb, size_t size)
 }
 
 /*
+** Free a pointer and set it to NULL.
+*/
+void
+mh_free0(void * ptr)
+{
+       void ** p;
+       p = ptr;
+       free(*p);
+       *p = NULL;
+}
+
+/*
 ** Return the present working directory, if the current directory does not
 ** exist, or is too long, make / the pwd.
 */
@@ -95,14 +107,14 @@ pwd(void)
 /*
 ** add   -- If "s1" is NULL, this routine just creates a
 **       -- copy of "s2" into newly malloc'ed memory.
-**       -- (use getcpy() instead in this case)
+**       -- (use mh_xstrdup() instead in this case)
 **       --
 **       -- If "s1" is not NULL, then copy the concatenation
 **       -- of "s1" and "s2" (note the order) into newly
 **       -- malloc'ed memory.  Then free "s1".
 */
 char *
-add(char *s2, char *s1)
+add(const char *s2, char *s1)
 {
        char *cp;
        size_t len1 = 0, len2 = 0;
@@ -119,7 +131,7 @@ add(char *s2, char *s1)
        /* Copy s1 and free it */
        if (s1) {
                memcpy(cp, s1, len1);
-               free(s1);
+               mh_free0(&s1);
        }
 
        /* Copy s2 */
@@ -155,7 +167,7 @@ create_folder(char *folder, int autocreate, void (*done_callback)(int))
                        if (!getanswer(cp)) {
                                done_callback(EX_CANTCREAT);
                        }
-                       free(cp);
+                       mh_free0(&cp);
                } else if (autocreate == -1) {
                        /* do not create, so exit */
                        done_callback(EX_CANTCREAT);
@@ -206,3 +218,19 @@ app_msgarg(struct msgs_array *msgs, char *cp)
        }
        msgs->msgs[msgs->size++] = cp;
 }
+
+/*
+** mh_xstrdup() is a wrapper of strdup() to replace getcpy().  It returns
+** a copy of its argument if this is nonnull; otherwise, it returns a
+** string of length 0.
+*/
+char *
+mh_xstrdup(char * s)
+{
+       char * tmp;
+       tmp = strdup(s ? s : "");
+       if (!tmp) {
+               adios(EX_OSERR, "strdup", "can't copy string");
+       }
+       return tmp;
+}