configure.ac: Test for libtinfo to resolve setupterm(3).

[nmh] / sbr / utils.c

diff --git a/sbr/utils.c b/sbr/utils.c
index 90f36bd340ef8cfd9eab9aed71f71a0b68e2f6d1..dd87532586586d1d9090a860a7b0be622a4da259 100644 (file)
--- a/sbr/utils.c
+++ b/sbr/utils.c
@@ -12,6 +12,7 @@
 #include "makedir.h"
 #include <fcntl.h>
 #include <limits.h>
+#include "read_line.h"
 
 extern char *mhdocdir;
 
@@ -47,7 +48,7 @@ void *mh_xrealloc(void *ptr, size_t size)
 
     /* Copy POSIX behaviour, coping with non-POSIX systems. */
     if (size == 0) {
-        mh_xfree(ptr);
+        free(ptr);
         return mh_xmalloc(1); /* Get a unique pointer. */
     }
     if (!ptr)
@@ -88,13 +89,6 @@ char *mh_xstrdup(const char *src)
     return dest;
 }
 
-/* Call free(3), if ptr isn't NULL. */
-void mh_xfree(void *ptr)
-{
-    if (ptr)
-        free(ptr); /* Some very old platforms can't cope with NULL. */
-}
-
 /*
  * Return the present working directory, if the current directory does not
  * exist, or is too long, make / the pwd.
@@ -123,13 +117,15 @@ pwd(void)
     return curwd;
 }
 
-/*
- * add   -- If "s1" is NULL, this routine just creates a
- *       -- copy of "s2" into newly malloc'ed memory.
- *       --
- *       -- If "s1" is not NULL, then copy the concatenation
- *       -- of "s1" and "s2" (note the order) into newly
- *       -- malloc'ed memory.  Then free "s1".
+/* add returns a newly malloc'd string, exiting on failure.  The order
+ * of the parameters is unusual.  A NULL parameter is treated as an
+ * empty string.  s1 is free'd.  Use mh_xstrdup(s) rather than add(s,
+ * NULL), with FENDNULL() if s might be NULL.
+ *
+ *     add(NULL, NULL) -> ""
+ *     add(NULL, "foo") -> "foo"
+ *     add("bar", NULL) -> "bar"
+ *     add("bar", "foo") -> "foobar"
  */
 char *
 add (const char *s2, char *s1)
@@ -532,24 +528,30 @@ nmh_version_changed (int older) {
 }
 
 
-/*
- * Scan for any 8-bit characters.  Return 1 if they exist.
- *
- * Scan up until the given endpoint (but not the actual endpoint itself).
- * If the endpoint is NULL, scan until a '\0' is reached.
- */
-
-int
-contains8bit(const char *start, const char *end)
+/* contains8bit returns true if any byte from start onwards fails
+ * isascii(3), i.e. is outside [0, 0x7f].  If start is NULL it returns
+ * false.  Bytes are examined until a NUL byte, or, if end is not NULL,
+ * whilst start is before end. */
+bool contains8bit(const char *start, const char *end)
 {
-    if (! start)
-       return 0;
+    const char *p;
+    char c;
 
-    while (*start != '\0' && (!end || (start < end)))
-       if (! isascii((unsigned char) *start++))
-           return 1;
+    if (!start)
+        return false;
 
-    return 0;
+    p = start;
+    if (end) {
+        while (p < end && (c = (*p++)))
+            if (!isascii((unsigned char)c))
+                return true;
+    } else {
+        while ((c = (*p++)))
+            if (!isascii((unsigned char)c))
+                return true;
+    }
+
+    return false;
 }