From ca18351173b1b0f40676f4b4373138f2202cd2e1 Mon Sep 17 00:00:00 2001
From: ChatN0ir <lacostejustin2@gmail.com>
Date: Mon, 14 Oct 2019 17:49:03 +0200
Subject: [PATCH] Fixed CRC-32 Error

---
 hash/hash.c         | 27 ++++++++++-----------------
 hash/hash.h         |  5 +++--
 hash/test_program.c |  1 +
 3 files changed, 14 insertions(+), 19 deletions(-)

diff --git a/hash/hash.c b/hash/hash.c
index 8f202d4bb..b8a4b37f1 100644
--- a/hash/hash.c
+++ b/hash/hash.c
@@ -63,25 +63,18 @@ int adler_32(char s[])
 }
 
 /* crc32 Hash-Algorithm*/
+#include <inttypes.h>
 
-int crc32(char string[])
-{
+uint32_t crc32(char* data){
     int i = 0;
-    unsigned int cur_crc, masking;
-
-    cur_crc = 0xFFFFFFFF;
-
-    while(string[i] != '\0')
-    {
-        unsigned int byte = string[i];
-        cur_crc = cur_crc ^ byte;
+    uint32_t crc = 0xffffffff;
+    while(data[i] != '\0'){
+        uint8_t byte = data[i];
+        crc = crc ^ byte;
         for(int j = 8; j > 0; --j)
-        {
-            masking = -(cur_crc & 1);
-            cur_crc = (cur_crc >> 1) ^ (0xEDB88320 & masking);
-        }
+            crc = (crc >> 1) ^ (0xEDB88320 & ( -(crc & 1)));
+
         i++;
     }
-
-    return -cur_crc;
-}
+    return crc ^ 0xffffffff;
+}
\ No newline at end of file
diff --git a/hash/hash.h b/hash/hash.h
index 1f0722ff0..8d2e80919 100644
--- a/hash/hash.h
+++ b/hash/hash.h
@@ -41,10 +41,11 @@ char xor8(char[]);
 int adler_32(char[]);
 
 /*
-    crc32: implements the crc-32 hash-algorithm
-    returns the checksum byte for the passed byte
+    crc32: implements the crc-32 checksum-algorithm
+    returns the crc-32 checksum
 */
 int crc32(char[]);
 
 
+
 #endif
\ No newline at end of file
diff --git a/hash/test_program.c b/hash/test_program.c
index 54439e8e4..b799135b6 100644
--- a/hash/test_program.c
+++ b/hash/test_program.c
@@ -16,6 +16,7 @@ int main(void)
     printf("xor8: %s --> %i\n", s, xor8(s)); /* 8 bit */
     printf("adler_32: %s --> %i\n", s, adler_32(s)); /* 32 bit */
     printf("crc32: %s --> %i\n", s, crc32(s));
+    
 
     return 0;
 }
\ No newline at end of file