Use void* to store function pointer when compiled as C23.

[0] decided that `rettype (*foo)();` must now be interpreted as
`rettype (*foo)(void);`. Luckily it also allows now to store function
pointers in a `void*` (c.f. Ch. J.5.7).

[0]: https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3096.pdf

Signed-off-by: Steffen Jaeckel <s@jaeckel.eu>

.github/workflows/main.yml

@@ -10,7 +10,7 @@ on:
 
 jobs:
   linux-tests:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-24.04
     strategy:
       matrix:
         valgrind:
@@ -46,7 +46,7 @@ jobs:
           cat test-suite*.log || true
 
   xssl-tests:
-    runs-on: ubuntu-22.04
+    runs-on: ubuntu-24.04
     strategy:
       matrix:
         xssl_versions:
@@ -142,7 +142,7 @@ jobs:
           cat testerr.log || true
 
   code-style:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-24.04
     name: Check coding style
     continue-on-error: true
     steps:

configure.ac

@@ -18,9 +18,10 @@ PKG_PROG_PKG_CONFIG
 
 AC_CANONICAL_HOST
 AS_CASE([$host_os],
+    [dragonfly*],  [PLATFORM="bsd"],
     [freebsd*],    [PLATFORM="bsd"],
-    [openbsd*],    [PLATFORM="bsd"],
     [netbsd*],     [PLATFORM="bsd"],
+    [openbsd*],    [PLATFORM="bsd"],
     [*nto*|*qnx*], [PLATFORM="qnx"],
     [*solaris*],   [PLATFORM="solaris"],
     [*android*],   [PLATFORM="android"],

src/common.h

@@ -30,12 +30,17 @@
 #include "snprintf.h"
 
 /** handlers **/
+#if (__STDC_VERSION__ >= 202000L)
+typedef void* xmpp_void_handler;
+#else
+typedef int (*xmpp_void_handler)();
+#endif
 
 typedef struct _xmpp_handlist_t xmpp_handlist_t;
 struct _xmpp_handlist_t {
     /* common members */
     int user_handler;
-    int (*handler)();
+    xmpp_void_handler handler;
     void *userdata;
     int enabled; /* handlers are added disabled and enabled after the
                   * handler chain is processed to prevent stanzas from

src/event.c

@@ -39,7 +39,7 @@
 #include <sys/select.h>
 #include <errno.h>
 #include <unistd.h>
-#define _sleep(x) usleep((x)*1000)
+#define _sleep(x) usleep((x) * 1000)
 #else
 #include <winsock2.h>
 #ifndef ETIMEDOUT

src/handler.c

@@ -25,8 +25,6 @@
 #include "common.h"
 #include "ostypes.h"
 
-typedef int (*xmpp_void_handler)();
-
 /* Remove item from the list pointed by head, but don't free it.
  * There can be a situation when user's handler deletes another handler which
  * is the previous in the list. handler_fire_stanza() and handler_fire_timed()

src/md5.c

@@ -37,7 +37,7 @@
 
 #define PUT_32BIT_LSB_FIRST(cp, value)    \
     do {                                  \
-        (cp)[0] = (value)&0xFF;           \
+        (cp)[0] = (value) & 0xFF;         \
         (cp)[1] = ((value) >> 8) & 0xFF;  \
         (cp)[2] = ((value) >> 16) & 0xFF; \
         (cp)[3] = ((value) >> 24) & 0xFF; \

src/rand.c

@@ -68,9 +68,9 @@ struct _xmpp_rand_t {
 };
 
 /* returns smallest number mupliple of y that not less than x */
-#define round_up(x, y) (((x) + (y)-1) / (y) * (y))
+#define round_up(x, y) (((x) + (y) - 1) / (y) * (y))
 /* returns smallest integer number that not less than x/y */
-#define div_round_up(x, y) (((x) + (y)-1) / (y))
+#define div_round_up(x, y) (((x) + (y) - 1) / (y))
 
 /* adds two arrays as numbers in big-endian representation and stores
  * result in the first one.

src/resolver.c

@@ -630,7 +630,7 @@ static void netbuf_add_16bitnum(unsigned char *buf,
 
     /* assuming big endian */
     *p++ = (num >> 8) & 0xff;
-    *p++ = (num)&0xff;
+    *p++ = (num) & 0xff;
 
     *offset += 2;
 }

src/sha.h

@@ -53,7 +53,7 @@ extern "C" {
         (y)[0] = (uint8_t)(((x) >> 24) & 255); \
         (y)[1] = (uint8_t)(((x) >> 16) & 255); \
         (y)[2] = (uint8_t)(((x) >> 8) & 255);  \
-        (y)[3] = (uint8_t)((x)&255);           \
+        (y)[3] = (uint8_t)((x) & 255);         \
     } while (0)
 
 #define LOAD32H(x, y)                                                     \
@@ -72,7 +72,7 @@ extern "C" {
         (y)[4] = (uint8_t)(((x) >> 24) & 255); \
         (y)[5] = (uint8_t)(((x) >> 16) & 255); \
         (y)[6] = (uint8_t)(((x) >> 8) & 255);  \
-        (y)[7] = (uint8_t)((x)&255);           \
+        (y)[7] = (uint8_t)((x) & 255);         \
     } while (0)
 
 #define LOAD64H(x, y)                                                         \
@@ -96,13 +96,13 @@ extern "C" {
 #define CONST64(n) n##ULL
 #endif
 
-#define RORc(x, y)                                           \
-    (((((uint32_t)(x)&0xFFFFFFFFUL) >> (uint32_t)((y)&31)) | \
-      ((uint32_t)(x) << (uint32_t)((32 - ((y)&31)) & 31))) & \
+#define RORc(x, y)                                               \
+    (((((uint32_t)(x) & 0xFFFFFFFFUL) >> (uint32_t)((y) & 31)) | \
+      ((uint32_t)(x) << (uint32_t)((32 - ((y) & 31)) & 31))) &   \
      0xFFFFFFFFUL)
-#define ROR64c(x, y)                                                       \
-    (((((x)&CONST64(0xFFFFFFFFFFFFFFFF)) >> ((uint64_t)(y)&CONST64(63))) | \
-      ((x) << (((uint64_t)64 - ((y)&63)) & 63))) &                         \
+#define ROR64c(x, y)                                                           \
+    (((((x) & CONST64(0xFFFFFFFFFFFFFFFF)) >> ((uint64_t)(y) & CONST64(63))) | \
+      ((x) << (((uint64_t)64 - ((y) & 63)) & 63))) &                           \
      CONST64(0xFFFFFFFFFFFFFFFF))
 
 #ifdef __cplusplus

src/sha256.c

@@ -9,7 +9,7 @@
 #define Ch(x, y, z) (z ^ (x & (y ^ z)))
 #define Maj(x, y, z) (((x | y) & z) | (x & y))
 #define S(x, n) RORc((x), (n))
-#define R(x, n) (((x)&0xFFFFFFFFUL) >> (n))
+#define R(x, n) (((x) & 0xFFFFFFFFUL) >> (n))
 #define Sigma0(x) (S(x, 2) ^ S(x, 13) ^ S(x, 22))
 #define Sigma1(x) (S(x, 6) ^ S(x, 11) ^ S(x, 25))
 #define Gamma0(x) (S(x, 7) ^ S(x, 18) ^ R(x, 3))

src/sha512.c

@@ -52,7 +52,7 @@ static const uint64_t K[80] = {
 #define Ch(x, y, z) (z ^ (x & (y ^ z)))
 #define Maj(x, y, z) (((x | y) & z) | (x & y))
 #define S(x, n) ROR64c(x, n)
-#define R(x, n) (((x)&CONST64(0xFFFFFFFFFFFFFFFF)) >> ((uint64_t)n))
+#define R(x, n) (((x) & CONST64(0xFFFFFFFFFFFFFFFF)) >> ((uint64_t)n))
 #define Sigma0(x) (S(x, 28) ^ S(x, 34) ^ S(x, 39))
 #define Sigma1(x) (S(x, 14) ^ S(x, 18) ^ S(x, 41))
 #define Gamma0(x) (S(x, 1) ^ S(x, 8) ^ R(x, 7))