Don't assume that "char" is signed.

For the C standard char can be either signed or unsigned, it's up to the
compiler, but Redis assumed that it was signed in a few places.

The practical effect of this patch is that now Redis 2.6 will run
correctly in every system where char is unsigned, notably the RaspBerry
PI and other ARM systems with GCC.

Thanks to Georgi Marinov (@eesn on twitter) that reported the problem
and allowed me to use his RaspBerry via SSH to trace and fix the issue!

diff --git a/src/bitops.c b/src/bitops.c
index 00192b92b14fc13194ded59143b1f2a9582e8871..deec0971d3001876cdadc4661a940f1dd518e3b2 100644 (file)
--- a/src/bitops.c
+++ b/src/bitops.c
@@ -114,14 +114,14 @@ void setbitCommand(redisClient *c) {
     o->ptr = sdsgrowzero(o->ptr,byte+1);
 
     /* Get current values */
-    byteval = ((char*)o->ptr)[byte];
+    byteval = ((uint8_t*)o->ptr)[byte];
     bit = 7 - (bitoffset & 0x7);
     bitval = byteval & (1 << bit);
 
     /* Update byte with new bit value and return original value */
     byteval &= ~(1 << bit);
     byteval |= ((on & 0x1) << bit);
-    ((char*)o->ptr)[byte] = byteval;
+    ((uint8_t*)o->ptr)[byte] = byteval;
     signalModifiedKey(c->db,c->argv[1]);
     server.dirty++;
     addReply(c, bitval ? shared.cone : shared.czero);
@@ -148,7 +148,7 @@ void getbitCommand(redisClient *c) {
             bitval = llbuf[byte] & (1 << bit);
     } else {
         if (byte < sdslen(o->ptr))
-            bitval = ((char*)o->ptr)[byte] & (1 << bit);
+            bitval = ((uint8_t*)o->ptr)[byte] & (1 << bit);
     }
 
     addReply(c, bitval ? shared.cone : shared.czero);

diff --git a/src/ziplist.c b/src/ziplist.c
index 50167651ba1d568940b05f2f2f86abafd9e5dffc..76a2cdde040068d9d575f4c4cacfd3f9c0a6e2d1 100644 (file)
--- a/src/ziplist.c
+++ b/src/ziplist.c
@@ -317,7 +317,7 @@ static void zipSaveInteger(unsigned char *p, int64_t value, unsigned char encodi
     int32_t i32;
     int64_t i64;
     if (encoding == ZIP_INT_8B) {
-        ((char*)p)[0] = (char)value;
+        ((int8_t*)p)[0] = (int8_t)value;
     } else if (encoding == ZIP_INT_16B) {
         i16 = value;
         memcpy(p,&i16,sizeof(i16));
@@ -325,7 +325,7 @@ static void zipSaveInteger(unsigned char *p, int64_t value, unsigned char encodi
     } else if (encoding == ZIP_INT_24B) {
         i32 = value<<8;
         memrev32ifbe(&i32);
-        memcpy(p,((unsigned char*)&i32)+1,sizeof(i32)-sizeof(int8_t));
+        memcpy(p,((uint8_t*)&i32)+1,sizeof(i32)-sizeof(uint8_t));
     } else if (encoding == ZIP_INT_32B) {
         i32 = value;
         memcpy(p,&i32,sizeof(i32));
@@ -347,7 +347,7 @@ static int64_t zipLoadInteger(unsigned char *p, unsigned char encoding) {
     int32_t i32;
     int64_t i64, ret = 0;
     if (encoding == ZIP_INT_8B) {
-        ret = ((char*)p)[0];
+        ret = ((int8_t*)p)[0];
     } else if (encoding == ZIP_INT_16B) {
         memcpy(&i16,p,sizeof(i16));
         memrev16ifbe(&i16);
@@ -358,7 +358,7 @@ static int64_t zipLoadInteger(unsigned char *p, unsigned char encoding) {
         ret = i32;
     } else if (encoding == ZIP_INT_24B) {
         i32 = 0;
-        memcpy(((unsigned char*)&i32)+1,p,sizeof(i32)-sizeof(int8_t));
+        memcpy(((uint8_t*)&i32)+1,p,sizeof(i32)-sizeof(uint8_t));
         memrev32ifbe(&i32);
         ret = i32>>8;
     } else if (encoding == ZIP_INT_64B) {