[PATCH v7 6/6] mspatcha: Fix binary to hex string conversions for GetFilePatchSignatureByBuffer

[ajkhoury]

From: ajkhoury

---
 dlls/mspatcha/mspatcha_main.c | 26 ++++++++++++++++++++------
 1 file changed, 20 insertions(+), 6 deletions(-)

diff --git a/dlls/mspatcha/mspatcha_main.c b/dlls/mspatcha/mspatcha_main.c
index 1d8744a85e4..9a184cf148d 100644
--- a/dlls/mspatcha/mspatcha_main.c
+++ b/dlls/mspatcha/mspatcha_main.c
@@ -54,14 +54,28 @@ static WCHAR *strdupAW(const char *src)
     return dst;
 }

-#define NIBBLE_CHAR(n) ((n) < 0xA) ? ('0' + (n)) : ('a' + ((n) - 0xA))
+static inline char nibble2char(unsigned char n)
+{
+    return (char)((n) < 0xA) ? ('0' + (n)) : ('a' + ((n) - 0xA));
+}
+
 static inline void bin2hex(const unsigned char *bin, char *hexstr, size_t maxcount)
 {
-    for (size_t i = 0; i < maxcount; i++) {
-        *hexstr++ = NIBBLE_CHAR((*bin >> 4) & 0xf);
-        *hexstr++ = NIBBLE_CHAR(*bin++ & 0xf);
+    size_t i, n = 0;
+    for (i = 0; i < maxcount; i++) {
+        hexstr[n++] = nibble2char((bin[i] >> 4) & 0xf);
+        hexstr[n++] = nibble2char((bin[i] & 0xf));
+    }
+    hexstr[n] = '\0';
+}
+
+static inline void dword2hex(unsigned int value, char *hexstr)
+{
+    size_t i;
+    for (i = 8; i > 0; --i, value >>= 4) {
+        hexstr[i-1] = nibble2char((value & 0xf));
     }
-    *hexstr = '\0';
+    hexstr[8] = '\0';
 }

/*****************************************************
@@ -403,7 +417,7 @@ BOOL WINAPI GetFilePatchSignatureByBuffer(
             if (signature_bufsize >= (sizeof(UINT32)*2+1)) {
                 /* calculate CRC32 checksum of file buffer. */
                 filecrc = RtlComputeCrc32(0, file_buffer, file_size);
-                bin2hex((const unsigned char *)&filecrc, signature_buf, sizeof(UINT32));
+                dword2hex(filecrc, signature_buf);

} else {
                 SetLastError(ERROR_INSUFFICIENT_BUFFER);