From 70a804e90f24b043d8ce8eafd792e9bc61a21f10 Mon Sep 17 00:00:00 2001
From: Matthew Budd <mjbudd77@gmail.com>
Date: Fri, 8 May 2020 23:30:31 -0400
Subject: [PATCH] Fixed a few code errors identified by cppcheck static code
 analyzer. Fixed incorrect error handling of realloc function to prevent
 memory leak. Fixed a few uninitialized local stack variables. Changed (1 <<
 31) to (1u << 31) to fix error stating that a signed 32 bit integer shifted
 by 31 bits can result in undefined behavior.

---
 src/emufile.cpp       |  6 +++---
 src/file.cpp          | 14 +++++++++-----
 src/utils/endian.cpp  |  6 +++---
 src/utils/general.cpp |  6 +++---
 4 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/src/emufile.cpp b/src/emufile.cpp
index 162e8df0..e0e83115 100644
--- a/src/emufile.cpp
+++ b/src/emufile.cpp
@@ -133,7 +133,7 @@ void EMUFILE::write64le(u64 val)
 
 size_t EMUFILE::read64le(u64 *Bufo)
 {
-	u64 buf;
+	u64 buf=0;
 	if(fread((char*)&buf,8) != 8)
 		return 0;
 #ifndef LOCAL_BE
@@ -174,7 +174,7 @@ size_t EMUFILE::read32le(s32* Bufo) { return read32le((u32*)Bufo); }
 
 size_t EMUFILE::read32le(u32* Bufo)
 {
-	u32 buf;
+	u32 buf=0;
 	if(fread(&buf,4)<4)
 		return 0;
 #ifndef LOCAL_BE
@@ -213,7 +213,7 @@ size_t EMUFILE::read16le(s16* Bufo) { return read16le((u16*)Bufo); }
 
 size_t EMUFILE::read16le(u16* Bufo)
 {
-	u32 buf;
+	u32 buf=0;
 	if(fread(&buf,2)<2)
 		return 0;
 #ifndef LOCAL_BE
diff --git a/src/file.cpp b/src/file.cpp
index 9860d87e..dfbba02e 100644
--- a/src/file.cpp
+++ b/src/file.cpp
@@ -104,12 +104,14 @@ void ApplyIPS(FILE *ips, FCEUFILE* fp)
 			if((offset+size)>(uint32)fp->size)
 			{
 				// Probably a little slow.
-				buf=(char *)realloc(buf,offset+size);
-				if(!buf)
+				char *newbuf=(char *)realloc(buf,offset+size);
+				if(!newbuf)
 				{
+					free(buf); buf=NULL;
 					FCEU_printf("  Oops.  IPS patch %d(type RLE) goes beyond end of file.  Could not allocate memory.\n",count);
 					goto end;
 				}
+				buf=newbuf;
 				memset(buf+fp->size,0,offset+size-fp->size);
 				fp->size=offset+size;
 			}
@@ -127,12 +129,14 @@ void ApplyIPS(FILE *ips, FCEUFILE* fp)
 			if((offset+size)>(uint32)fp->size)
 			{
 				// Probably a little slow.
-				buf=(char *)realloc(buf,offset+size);
-				if(!buf)
+				char *newbuf=(char *)realloc(buf,offset+size);
+				if(!newbuf)
 				{
+					free(buf); buf=NULL;
 					FCEU_printf("  Oops.  IPS patch %d(type normal) goes beyond end of file.  Could not allocate memory.\n",count);
 					goto end;
 				}
+				buf=newbuf;
 				memset(buf+fp->size,0,offset+size-fp->size);
 			}
 			fread(buf+offset,1,size,ips);
@@ -475,9 +479,9 @@ void FCEUI_SetDirOverride(int which, char *n)
 		va_list ap;
 		int ret;
 
-		va_start(ap,fmt);
 		if(!(*strp=(char*)FCEU_dmalloc(2048))) //mbg merge 7/17/06 cast to char*
 			return(0);
+		va_start(ap,fmt);
 		ret=vsnprintf(*strp,2048,fmt,ap);
 		va_end(ap);
 		return(ret);
diff --git a/src/utils/endian.cpp b/src/utils/endian.cpp
index 71732ff1..56704d41 100644
--- a/src/utils/endian.cpp
+++ b/src/utils/endian.cpp
@@ -275,7 +275,7 @@ int write64le(uint64 b, EMUFILE* os)
 
 int read32le(uint32 *Bufo, EMUFILE *fp)
 {
-	uint32 buf;
+	uint32 buf=0;
 	if(fp->_fread(&buf,4)<4)
 		return 0;
 #ifdef LOCAL_LE
@@ -288,7 +288,7 @@ int read32le(uint32 *Bufo, EMUFILE *fp)
 
 int read16le(u16 *Bufo, EMUFILE *is)
 {
-	u16 buf;
+	u16 buf=0;
 	if(is->_fread((char*)&buf,2) != 2)
 		return 0;
 #ifdef LOCAL_LE
@@ -301,7 +301,7 @@ int read16le(u16 *Bufo, EMUFILE *is)
 
 int read64le(uint64 *Bufo, EMUFILE *is)
 {
-	uint64 buf;
+	uint64 buf=0;
 	if(is->_fread((char*)&buf,8) != 8)
 		return 0;
 #ifdef LOCAL_LE
diff --git a/src/utils/general.cpp b/src/utils/general.cpp
index c84d9e70..9f49a19b 100644
--- a/src/utils/general.cpp
+++ b/src/utils/general.cpp
@@ -28,10 +28,10 @@ uint32 uppow2(uint32 n)
  int x;
 
  for(x=31;x>=0;x--)
-  if(n&(1<<x))
+  if(n&(1u<<x))
   {
-   if((1<<x)!=n)
-    return(1<<(x+1));
+   if((1u<<x)!=n)
+    return(1u<<(x+1));
    break;
   }
  return n;