Add timeout

Makefile

@@ -14,6 +14,6 @@ $(TARGET): $(OBJECTS)
 	$(CC) -c $(CFLAGS) $< -o $@
 
 clean:
-	rm -f *.o libnvram.so
+	rm -f *.o libnvram.so test
 
 .PHONY: clean

config.h

@@ -15,6 +15,8 @@
 #define LIST_MAGIC          0xdeadbeef
 // Identifier value used to generate IPC key in ftok()
 #define IPC_KEY             'A'
+// Timeout for the semaphore
+#define IPC_TIMEOUT         1000
 // Mount point of the base NVRAM implementation.
 #define MOUNT_POINT         "/firmadyne/libnvram/"
 // Location of NVRAM override values that are copied into the base NVRAM implementation.

nvram.c

@@ -43,6 +43,7 @@ static char temp[BUFFER_SIZE];
 
 static int sem_get() {
     int key, semid = 0;
+    unsigned int timeout = 0;
     struct semid_ds seminfo;
     union semun {
         int val;
@@ -74,8 +75,7 @@ static int sem_get() {
             semctl(semid, 0, IPC_RMID);
             semid = -1;
         }
-    }
-    else if (errno == EEXIST) {
+    } else if (errno == EEXIST) {
         // Get the semaphore in non-exclusive mode
         if ((semid = semget(key, 1, 0)) < 0) {
             PRINT_MSG("%s\n", "Unable to get semaphore non-exclusively!");
@@ -84,18 +84,20 @@ static int sem_get() {
 
         semun.buf = &seminfo;
         // Wait for the semaphore to be initialized
-        while (1) {
+        while (timeout++ < IPC_TIMEOUT) {
             semctl(semid, 0, IPC_STAT, semun);
 
             if (semun.buf && semun.buf->sem_otime != 0) {
                 break;
             }
 
-            PRINT_MSG("Waiting for semaphore initialization (Key: %x, Semaphore: %x)...\n", key, semid);
+            if (!(timeout % 100)) {
+                PRINT_MSG("Waiting for semaphore initialization (Key: %x, Semaphore: %x)...\n", key, semid);
+            }
         }
     }
 
-    return semid;
+    return (timeout < IPC_TIMEOUT) ? semid : -1;
 }
 
 static void sem_lock() {

test.c

@@ -0,0 +1,56 @@
+#include <stdio.h>
+
+#include "nvram.h"
+
+// Prototypes from "alias.c"
+char *nvram_nget(const char *fmt, ...);
+int nvram_nset(const char *val, const char *fmt, ...);
+int foreach_nvram_from(const char *file, void (*fp)(const char *, const char *, void *), void *data);
+
+
+void test(const char *key, const char*val, void* data) {
+    printf("%s = %s, %s\n", key, val, (char *) data);
+}
+
+int main(int argc, char** argv) {
+    char buf[256], *ptr;
+    int tmp;
+
+    nvram_init();
+
+    nvram_clear();
+
+    nvram_set_default();
+
+    nvram_getall(buf, 256);
+
+    nvram_set("str", "test");
+
+    nvram_set_int("int", 2048);
+
+    ptr = nvram_get("str");
+
+    tmp = nvram_get_int("int");
+
+    nvram_commit();
+
+    nvram_getall(buf, 256);
+
+    nvram_reset();
+
+    ptr = nvram_get("is_default");
+
+    nvram_close();
+
+    nvram_unset("is_default");
+
+    ptr = nvram_get("is_default");
+
+    nvram_nset("test", "%s_file", "a");
+
+    ptr = nvram_nget("%s_file", "a");
+
+    foreach_nvram_from("/tmp/test.ini", test, "5");
+
+    return 0;
+}