Make strishex() library function

git-svn-id: http://svn.code.sf.net/p/netpbm/code/trunk@38 9d0c8265-081b-0410-96cb-a4ca84ce46f8

2 files changed, 21 insertions, 0 deletions

diff --git a/lib/util/nstring.c b/lib/util/nstring.c
index 749e9060..58500547 100644
--- a/lib/util/nstring.c
+++ b/lib/util/nstring.c
@@ -895,3 +895,20 @@ memmemN(const char * const haystack,
 
     return NULL;
 }
+
+
+
+bool
+strishex(const char * const subject) {
+
+    bool retval;
+    unsigned int i;
+
+    retval = TRUE;  /* initial assumption */
+
+    for (i = 0; i < strlen(subject); ++i)
+        if (!ISXDIGIT(subject[i]))
+            retval = FALSE;
+
+    return retval;
+}
diff --git a/lib/util/nstring.h b/lib/util/nstring.h
index d976e859..70a53f45 100644
--- a/lib/util/nstring.h
+++ b/lib/util/nstring.h
@@ -5,6 +5,7 @@
 #include <string.h>
 #include <ctype.h>
 
+#include "pm_c_util.h"
 #include "pm.h"  /* For PM_GNU_PRINTF_ATTR, __inline__ */
 
 #ifdef __cplusplus
@@ -155,6 +156,9 @@ memmemN(const char * const haystack,
         const char * const needle,
         size_t       const needlelen);
 
+bool
+strishex(const char * const subject);
+
 #ifdef __cplusplus
 }
 #endif