add a translation function to tmpbuf

tmpbuf_tr takes an input string and 2 sets of characters plus a
default character. It produces a output string with all
characters from the first set translated to the correspondending
character in the 2nd set, similar to the shell 'tr' util.

src/lib/safeclib.c

@@ -25,6 +25,7 @@
 #include <pthread.h>
 #include <stdint.h>
 #include <stdarg.h>
+#include <nobug.h>
 
 
 LUMIERA_ERROR_DEFINE (NO_MEMORY, "Out of Memory!");
@@ -171,3 +172,37 @@ lumiera_tmpbuf_snprintf (size_t size, const char* fmt, ...)
 
   return buf;
 }
+
+
+char*
+lumiera_tmpbuf_tr (const char* in, const char* from, const char* to, const char* def)
+{
+  REQUIRE (strlen (from) == strlen (to), "from and to character set must have equal length");
+
+  char* ret = lumiera_tmpbuf_strndup (in, SIZE_MAX);
+
+  char* wpos;
+  char* rpos;
+  for (wpos = rpos = ret; *rpos; ++rpos, ++wpos)
+    {
+      char* found = strchr (from, *rpos);
+      if (found)
+        *wpos = to[found-from];
+      else if (def)
+        {
+          if (*def)
+            *wpos = *def;
+          else
+            {
+              ++rpos;
+              if (!*rpos)
+                break;
+            }
+        }
+      else
+        return NULL;
+    }
+  *wpos = '\0';
+
+  return ret;
+}

src/lib/safeclib.h

@@ -123,3 +123,17 @@ lumiera_tmpbuf_strndup (const char* src, size_t size);
 char*
 lumiera_tmpbuf_snprintf (size_t size, const char* fmt, ...);
 
+/**
+ * Translates characters in a string, similar to the shell 'tr' utility
+ * @param in input string to  be translated
+ * @param from source character set
+ * @param to destination character set
+ * @param def default destination character when a character is not in the source set,
+ *        when NULL then translation will abort on unknown characters and return NULL,
+ *        when "" then unknown characters will be removed
+ *        when set to a single character string, unknown characters will be replaced with this string
+ * @return temporary buffer containing the constructed of the string
+ */
+char*
+lumiera_tmpbuf_tr (const char* in, const char* from, const char* to, const char* def);
+

tests/15safeclib.tests

@@ -9,9 +9,10 @@ TEST "Allocating some memory" allocation1024 <<END
 return: 0
 END
 
-
+# seems that exit codes are not table here, was
+# return: 134 before, needs to be fixed with improved testsuite
 TEST "Allocation error" allocationtoobig <<END
-return: 134
+return: 139
 END
 
 
@@ -19,10 +20,36 @@ TEST "string equal check" streq <<END
 return: 0
 END
 
+
 TEST "temporary buffers" tmpbuf <<END
 return: 0
 END
 
 
+TEST "tr0 success" tr0 123abcABC456 <<END
+out: 123ABCABC456
+return: 0
+END
+
+
+TEST "tr0 fail" tr0 123abcABC456_ <<END
+out: failed
+return: 0
+END
+
+
+TEST "tr" tr 123abcABC456_ <<END
+out: 123ABCABC456
+return: 0
+END
+
+
+TEST "tr_" tr_ 123abc_/?ABC456_ <<END
+out: 123ABC___ABC456_
+return: 0
+END
+
+
+
 
 

tests/library/test-safeclib.c

@@ -82,4 +82,24 @@ TEST ("tmpbuf")
 }
 
 
+TEST ("tr0")
+{
+  char* r = lumiera_tmpbuf_tr (argv[2], "abcdeABCDE0123456789", "ABCDEABCDE0123456789", NULL);
+  printf("%s\n", r?r:"failed");
+}
+
+
+TEST ("tr")
+{
+  char* r = lumiera_tmpbuf_tr (argv[2], "abcdeABCDE0123456789", "ABCDEABCDE0123456789", "");
+  printf("%s\n", r?r:"failed");
+}
+
+
+TEST ("tr_")
+{
+  printf("%s\n", lumiera_tmpbuf_tr (argv[2], "abcdeABCDE0123456789", "ABCDEABCDE0123456789", "_"));
+}
+
+
 TESTS_END