Abstract __attribute__((constructor))

Some platforms (e.g. macOS) do not support constructor priorities, so at least make them compile. Ideally, we'd register a function to be called at initialization the same way Lua modules are registered, and manage the order inside lwan_init(); but this is good for now.
lpereira · Aug 27, 2024 · af47365 · af47365
1 parent 953d765
commit af47365
Show file tree

Hide file tree

Showing 11 changed files with 24 additions and 12 deletions.
diff --git a/src/bin/tools/bin2hex.c b/src/bin/tools/bin2hex.c
@@ -26,11 +26,11 @@
 #include <sys/types.h>
 #include <unistd.h>
 
-#include "lwan.h"
+#include "lwan-private.h"
 
 static int constructor_attr_supported = 0;
 
-__attribute__((constructor))
+LWAN_CONSTRUCTOR()
 static void initialize_constructor_attr_supported(void)
 {
     constructor_attr_supported = 1;

diff --git a/src/lib/hash.c b/src/lib/hash.c
@@ -208,7 +208,8 @@ static inline unsigned int hash_int64_crc32(const void *keyptr)
 
 #endif
 
-__attribute__((constructor(65535))) static void initialize_fnv1a_seed(void)
+LWAN_CONSTRUCTOR(65535)
+static void initialize_fnv1a_seed(void)
 {
     uint8_t entropy[128];
 

diff --git a/src/lib/lwan-lua.c b/src/lib/lwan-lua.c
@@ -425,7 +425,7 @@ static int luaopen_log(lua_State *L)
 DEFINE_ARRAY_TYPE(lwan_lua_method_array, luaL_reg)
 static struct lwan_lua_method_array lua_methods;
 
-__attribute__((constructor))
+LWAN_CONSTRUCTOR()
 __attribute__((no_sanitize_address))
 static void register_lua_methods(void)
 {

diff --git a/src/lib/lwan-private.h b/src/lib/lwan-private.h
@@ -28,6 +28,12 @@
 #define DEFAULT_BUFFER_SIZE 4096
 #define DEFAULT_HEADERS_SIZE 2048
 
+#if defined(__APPLE__)
+# define LWAN_CONSTRUCTOR(prio_)	__attribute__((constructor))
+#else
+# define LWAN_CONSTRUCTOR(prio_)	__attribute__((constructor(prio_)))
+#endif
+
 struct lwan_request_parser_helper {
     struct lwan_value *buffer; /* The whole request buffer */
     char *next_request;        /* For pipelined requests */

diff --git a/src/lib/lwan-readahead.c b/src/lib/lwan-readahead.c
@@ -60,7 +60,8 @@ static pthread_t readahead_self;
 static long page_size = PAGE_SIZE;
 
 #ifdef _SC_PAGESIZE
-__attribute__((constructor)) static void get_page_size(void)
+LWAN_CONSTRUCTOR()
+static void get_page_size(void)
 {
     long ps = sysconf(_SC_PAGESIZE);
 

diff --git a/src/lib/lwan-request.c b/src/lib/lwan-request.c
@@ -1112,7 +1112,8 @@ get_temp_dir(void)
     return NULL;
 }
 
-__attribute__((constructor)) static void initialize_temp_dir(void)
+LWAN_CONSTRUCTOR()
+static void initialize_temp_dir(void)
 {
     temp_dir = get_temp_dir();
 }

diff --git a/src/lib/lwan-status.c b/src/lib/lwan-status.c
@@ -243,7 +243,8 @@ void lwan_syslog_status_out(
     lwan_strbuf_free(&buf);
 }
 
-__attribute__((constructor)) static void register_lwan_to_syslog(void)
+LWAN_CONSTRUCTOR()
+static void register_lwan_to_syslog(void)
 {
     openlog("lwan", LOG_NDELAY | LOG_PID | LOG_CONS, LOG_USER);
 }

diff --git a/src/lib/lwan.c b/src/lib/lwan.c
@@ -975,7 +975,8 @@ void lwan_main_loop(struct lwan *l)
 }
 
 #ifdef CLOCK_MONOTONIC_COARSE
-__attribute__((constructor)) static void detect_fastest_monotonic_clock(void)
+LWAN_CONSTRUCTOR()
+static void detect_fastest_monotonic_clock(void)
 {
     struct timespec ts;
 

diff --git a/src/samples/clock/blocks.c b/src/samples/clock/blocks.c
@@ -12,6 +12,7 @@
 #include <stdio.h>
 #include <string.h>
 
+#include "lwan-private.h"
 #include "blocks.h"
 
 enum shape {
@@ -175,7 +176,7 @@ static const struct fall *fall[] = {
 
 static int block_sizes[10];
 
-__attribute__((constructor)) void calculate_block_sizes(void)
+LWAN_CONSTRUCTOR() void calculate_block_sizes(void)
 {
     for (int i = 0; i < 10; i++) {
         const struct fall *instr = fall[i];

diff --git a/src/samples/clock/main.c b/src/samples/clock/main.c
@@ -21,7 +21,7 @@
 #include <stdlib.h>
 #include <limits.h>
 
-#include "lwan.h"
+#include "lwan-private.h"
 #include "lwan-template.h"
 #include "lwan-mod-redirect.h"
 #include "gifenc.h"
@@ -245,7 +245,7 @@ static const struct lwan_var_descriptor index_desc[] = {
 
 static struct lwan_tpl *index_tpl;
 
-__attribute__((constructor)) static void initialize_template(void)
+LWAN_CONSTRUCTOR() static void initialize_template(void)
 {
     static const char index[] =
         "<html>\n"

diff --git a/src/samples/clock/xdaliclock.c b/src/samples/clock/xdaliclock.c
@@ -155,7 +155,7 @@ frame_from_pixmap(const unsigned char *bits, int width, int height)
     return frame;
 }
 
-__attribute__((constructor)) static void initialize_numbers(void)
+LWAN_CONSTRUCTOR() static void initialize_numbers(void)
 {
     const struct raw_number *raw = get_raw_numbers();