removed a number of stupid compilation warnings on Linux

src/redis-check-dump.c

@@ -538,7 +538,8 @@ void printErrorStack(entry *e) {
 
     /* display error stack */
     for (i = 0; i < errors.level; i++) {
-        printf("0x%08lx - %s\n", errors.offset[i], errors.error[i]);
+        printf("0x%08lx - %s\n",
+            (unsigned long) errors.offset[i], errors.error[i]);
     }
 }
 

src/redis.c

@@ -1250,7 +1250,7 @@ void freeMemoryIfNeeded(void) {
         if (tryFreeOneObjectFromFreelist() == REDIS_OK) continue;
 
         for (j = 0; j < server.dbnum; j++) {
-            long bestval;
+            long bestval = 0; /* just to prevent warning */
             sds bestkey = NULL;
             struct dictEntry *de;
             redisDb *db = server.db+j;

src/ziplist.c

@@ -754,9 +754,9 @@ void ziplistRepr(unsigned char *zl) {
                 "pls: %2u, "
                 "payload %5u"
             "} ",
-            (long unsigned int)p,
+            (long unsigned)p,
             index,
-            p-zl,
+            (unsigned long) (p-zl),
             entry.headersize+entry.len,
             entry.headersize,
             entry.prevrawlen,
@@ -765,10 +765,11 @@ void ziplistRepr(unsigned char *zl) {
         p += entry.headersize;
         if (ZIP_IS_STR(entry.encoding)) {
             if (entry.len > 40) {
-                fwrite(p,40,1,stdout);
+                if (fwrite(p,40,1,stdout) == 0) perror("fwrite");
                 printf("...");
             } else {
-                fwrite(p,entry.len,1,stdout);
+                if (entry.len &&
+                    fwrite(p,entry.len,1,stdout) == 0) perror("fwrite");
             }
         } else {
             printf("%lld", (long long) zipLoadInteger(p,entry.encoding));
@@ -857,7 +858,7 @@ void pop(unsigned char *zl, int where) {
             printf("Pop tail: ");
 
         if (vstr)
-            fwrite(vstr,vlen,1,stdout);
+            if (vlen && fwrite(vstr,vlen,1,stdout) == 0) perror("fwrite");
         else
             printf("%lld", vlong);
 
@@ -932,7 +933,7 @@ int main(int argc, char **argv) {
             return 1;
         }
         if (entry) {
-            fwrite(entry,elen,1,stdout);
+            if (elen && fwrite(entry,elen,1,stdout) == 0) perror("fwrite");
             printf("\n");
         } else {
             printf("%lld\n", value);
@@ -962,7 +963,7 @@ int main(int argc, char **argv) {
             return 1;
         }
         if (entry) {
-            fwrite(entry,elen,1,stdout);
+            if (elen && fwrite(entry,elen,1,stdout) == 0) perror("fwrite");
             printf("\n");
         } else {
             printf("%lld\n", value);
@@ -979,7 +980,7 @@ int main(int argc, char **argv) {
             return 1;
         }
         if (entry) {
-            fwrite(entry,elen,1,stdout);
+            if (elen && fwrite(entry,elen,1,stdout) == 0) perror("fwrite");
             printf("\n");
         } else {
             printf("%lld\n", value);
@@ -1007,7 +1008,7 @@ int main(int argc, char **argv) {
         while (ziplistGet(p, &entry, &elen, &value)) {
             printf("Entry: ");
             if (entry) {
-                fwrite(entry,elen,1,stdout);
+                if (elen && fwrite(entry,elen,1,stdout) == 0) perror("fwrite");
             } else {
                 printf("%lld", value);
             }
@@ -1024,7 +1025,7 @@ int main(int argc, char **argv) {
         while (ziplistGet(p, &entry, &elen, &value)) {
             printf("Entry: ");
             if (entry) {
-                fwrite(entry,elen,1,stdout);
+                if (elen && fwrite(entry,elen,1,stdout) == 0) perror("fwrite");
             } else {
                 printf("%lld", value);
             }
@@ -1041,7 +1042,7 @@ int main(int argc, char **argv) {
         while (ziplistGet(p, &entry, &elen, &value)) {
             printf("Entry: ");
             if (entry) {
-                fwrite(entry,elen,1,stdout);
+                if (elen && fwrite(entry,elen,1,stdout) == 0) perror("fwrite");
             } else {
                 printf("%lld", value);
             }
@@ -1070,7 +1071,7 @@ int main(int argc, char **argv) {
         while (ziplistGet(p, &entry, &elen, &value)) {
             printf("Entry: ");
             if (entry) {
-                fwrite(entry,elen,1,stdout);
+                if (elen && fwrite(entry,elen,1,stdout) == 0) perror("fwrite");
             } else {
                 printf("%lld", value);
             }
@@ -1087,7 +1088,7 @@ int main(int argc, char **argv) {
         while (ziplistGet(p, &entry, &elen, &value)) {
             printf("Entry: ");
             if (entry) {
-                fwrite(entry,elen,1,stdout);
+                if (elen && fwrite(entry,elen,1,stdout) == 0) perror("fwrite");
             } else {
                 printf("%lld", value);
             }
@@ -1144,7 +1145,8 @@ int main(int argc, char **argv) {
             } else {
                 printf("Entry: ");
                 if (entry) {
-                    fwrite(entry,elen,1,stdout);
+                    if (elen && fwrite(entry,elen,1,stdout) == 0)
+                        perror("fwrite");
                 } else {
                     printf("%lld",value);
                 }

src/zipmap.c

@@ -374,14 +374,14 @@ void zipmapRepr(unsigned char *p) {
             l = zipmapDecodeLength(p);
             printf("{key %u}",l);
             p += zipmapEncodeLength(NULL,l);
-            fwrite(p,l,1,stdout);
+            if (l != 0 && fwrite(p,l,1,stdout) == 0) perror("fwrite");
             p += l;
 
             l = zipmapDecodeLength(p);
             printf("{value %u}",l);
             p += zipmapEncodeLength(NULL,l);
             e = *p++;
-            fwrite(p,l,1,stdout);
+            if (l != 0 && fwrite(p,l,1,stdout) == 0) perror("fwrite");
             p += l+e;
             if (e) {
                 printf("[");