C: create my own include file

c/phone-number/makefile

@@ -11,6 +11,7 @@ CFLAGS += -Wextra
 CFLAGS += -pedantic
 CFLAGS += -Werror
 CFLAGS += -Wmissing-declarations
+CFLAGS += -Wimplicit-fallthrough
 CFLAGS += -DUNITY_SUPPORT_64
 
 ASANFLAGS  = -fsanitize=address
@@ -34,4 +35,4 @@ clean:
 
 tests.out: test/*.c src/*.c src/*.h
 	@echo Compiling $@
-	@$(CC) $(CFLAGS) src/*.c test/vendor/unity.c test/*.c -o tests.out $(LIBS)
+	$(CC) $(CFLAGS) src/*.c test/vendor/unity.c test/*.c -o tests.out $(LIBS)

c/phone-number/src/phone_number.c

@@ -1,4 +1,3 @@
-#include <stdio.h>
 #include <stdlib.h>
 #include <malloc.h>
 #include <string.h>
@@ -10,15 +9,15 @@
 #define LPAREN    '('
 
 /* this version is likely not very stable, due to poor scanf() capabilities
- * I made it to offer an option to traditional strtok() of manual string
+ * I made it to offer an option to traditional strtok() or manual string
  * parsing.
  */
 char *phone_number_clean(const char *input)
 {
     char *scan="%m[+(0-9]%*[()-. ]%m[0-9]%*[()-. ]%m[0-9]%*[-. ]%m[0-9]";
     char *sn[4];
-    int64_t num[4];
-    int64_t *p = &num[0];
+    uint64_t num[4];
+    uint64_t *p = &num[0];
     int nmatch;
     char *res;
 
@@ -30,7 +29,7 @@ char *phone_number_clean(const char *input)
     nmatch = sscanf(input, scan, &sn[0], &sn[1], &sn[2], &sn[3]);
 
     for (int i=0; i<nmatch; ++i) {
-        num[i] = atol(*sn[i] == LPAREN? sn[i]+1: sn[i]);
+        *(p+i) = atol(*sn[i] == LPAREN? sn[i]+1: sn[i]);
         free(sn[i]);
     }
 
@@ -39,19 +38,21 @@ char *phone_number_clean(const char *input)
         case 0:
             return res;
         case 1:
-            if (num[0] > 10000000000)
-                num[0] -= 10000000000;
-            if (num[0] > 9999999999 || num[0] < 2000000000)
+            if (*p > 10000000000)                 /* 1 000 000 0000 */
+                *p -= 10000000000;
+            if (*p > 9999999999 ||                /* 999 999 9999 */
+                *p < 2000000000)                  /* 200 000 0000 */
                 return res;
             break;
         case 4:                                   /* area */
-            if (num[0] != 1)
+            if (*p != 1)
                 return res;
             p++;
-            fallthrough;
+            fallthrough;                          /* only gcc>=7 & clang>=12 */
         case 3:                                   /* last 3 numbers */
-            if (p[0] < 200 || p[0] > 999 || p[1] < 200 || p[1] > 999 ||
-                p[2] < 0 || p[2] > 9999)
+            if (*p < 200 || *p > 999 ||
+                *(p+1) < 200 || *(p+1) > 999 ||
+                *(p+2) > 9999)
                 return res;
             break;
     }

c/phone-number/src/phone_number.h

@@ -1,32 +1,10 @@
 #ifndef PHONE_NUMBER_H
 #define PHONE_NUMBER_H
 
+#include "br-common.h"
+
 #define NUMBER_LENGTH 10
 
 char *phone_number_clean(const char *input);
 
-/* from :
- * https://github.com/torvalds/linux/blob/master/include/linux/compiler_attributes.h
- * around line 200
- * should work with recent gcc/clang
- */
-#if __has_attribute(__fallthrough__)
-# define fallthrough                    __attribute__((__fallthrough__))
-#else
-# define fallthrough                    do {} while (0)  /* fallthrough */
-#endif
-
-/* See GNUmakefile below for explanation
- * https://github.com/braoult/exercism/blob/master/c/templates/GNUmakefile
- */
-#if defined UNIT_TEST || defined DEBUG
-#include <stdio.h>
-#include <stdlib.h>
-#endif
-
-#ifdef  TESTALL
-#undef  TEST_IGNORE
-#define TEST_IGNORE() {}
-#endif
-
 #endif

c/templates/ex.h

@@ -2,11 +2,11 @@
  * https://github.com/braoult/exercism/blob/master/c/templates/GNUmakefile
  */
 #if defined UNIT_TEST || defined DEBUG
-#include <stdio.h>
-#include <stdlib.h>
+# include <stdio.h>
+# include <stdlib.h>
 #endif
 
 #ifdef  TESTALL
-#undef  TEST_IGNORE
-#define TEST_IGNORE() {}
+# undef  TEST_IGNORE
+# define TEST_IGNORE() {}
 #endif