Clean up and fix error reporting of cc4group_uncompressGroup and cc4group_inflateFillOutput

1 files changed, 46 insertions, 30 deletions

diff --git a/src/cc4group.c b/src/cc4group.c
index 25e354d..0bc1029 100644
--- a/src/cc4group.c
+++ b/src/cc4group.c
@@ -46,6 +46,9 @@ static bool cc4group_getEntryData(CC4Group* const this, const char* const entryP
 #define C4GroupMagic1 0x1e
 #define C4GroupMagic2 0x8c
 
+#define CC4GROUP_UNEXPECTED_EOD -100
+#define CC4GROUP_MEM_ERROR -101
+
 typedef enum {
 	Take,
 	Copy,
@@ -136,10 +139,37 @@ static char* cc4group_strerrorFormatter(int32_t const code, const char* const me
 
 static char* cc4group_zerrorFormatter(int32_t const code, const char* const method, const char* const causer, void* const data)
 {
+	int storedErrno = (size_t)data;
 	// restore errno for the case that code is Z_ERRNO
-	errno = (size_t)data;
+	if(code == Z_ERRNO)
+	{
+		errno = storedErrno;
+	}
+
 	char* message;
-	asprintf(&message, "%s: %s: %s (%d)", method, causer, zError(code), code);
+	const char* errorString;
+
+	if(code == CC4GROUP_MEM_ERROR)
+	{
+		errorString = "";
+		asprintf(&message, "%s: %s: Can't allocate memory for copying the input data: %s (%d)", method, causer, strerror(storedErrno), storedErrno);
+		return message;
+	}
+
+	if(code == CC4GROUP_UNEXPECTED_EOD)
+	{
+		errorString = "Unexpected end of group data";
+	}
+	else if(code == Z_OK)
+	{
+		errorString = "Z_OK";
+	}
+	else
+	{
+		errorString = zError(code);
+	}
+
+	asprintf(&message, "%s: %s: %s (%d)", method, causer, errorString, code);
 	return message;
 }
 
@@ -371,7 +401,7 @@ static bool cc4group_inflateFillOutput(z_stream* const strm, CC4Group_ReadCallba
 		{
 			if(*eof)
 			{
-				*inflateRet = Z_OK;
+				*inflateRet = CC4GROUP_UNEXPECTED_EOD;
 				return false;
 			}
 
@@ -389,7 +419,11 @@ static bool cc4group_inflateFillOutput(z_stream* const strm, CC4Group_ReadCallba
 				continue;
 			}
 
-			cc4group_applyMemoryManagementStart(memoryManagement, lastData, readSize);
+			if(!cc4group_applyMemoryManagementStart(memoryManagement, lastData, readSize))
+			{
+				*inflateRet = CC4GROUP_MEM_ERROR;
+				return false;
+			}
 
 			strm->avail_in = readSize;
 			strm->next_in = (uint8_t*)*lastData; // I don't know why this must be non-const; anyway a read-only mapped input doesn't segfault. so it seems to be used read-only
@@ -462,8 +496,11 @@ static bool cc4group_uncompressGroup(CC4Group* const this, CC4Group_ReadCallback
 			continue;
 		}
 
-		// TODO: check for success at every call of this
-		cc4group_applyMemoryManagementStart(memoryManagement, &readData, readSize);
+		if(!cc4group_applyMemoryManagementStart(memoryManagement, &readData, readSize))
+		{
+			SET_ZERROR_ERROR("reading the group magic", CC4GROUP_MEM_ERROR);
+			goto ret;
+		}
 
 		size_t newTotalReadSize = totalReadSize + readSize;
 		if(totalReadSize < 1 && newTotalReadSize > 0)
@@ -538,14 +575,7 @@ static bool cc4group_uncompressGroup(CC4Group* const this, CC4Group_ReadCallback
 
 	if(!cc4group_inflateFillOutput(&strm, readCallback, callbackArg, memoryManagement, &eof, &readData, &ret))
 	{
-		if(eof && ret == Z_BUF_ERROR)
-		{
-			SET_EOD_ERROR("inflating group header");
-		}
-		else
-		{
-			SET_ZERROR_ERROR("inflate: inflating the group header", ret);
-		}
+		SET_ZERROR_ERROR("inflate: inflating the group header", ret);
 		goto ret;
 	}
 
@@ -598,14 +628,7 @@ static bool cc4group_uncompressGroup(CC4Group* const this, CC4Group_ReadCallback
 
 	if(!cc4group_inflateFillOutput(&strm, readCallback, callbackArg, memoryManagement, &eof, &readData, &ret))
 	{
-		if(eof && ret == Z_BUF_ERROR)
-		{
-			SET_EOD_ERROR("inflating the group entry dictionary");
-		}
-		else
-		{
-			SET_ZERROR_ERROR("inflate: inflating the group entry dictionary", ret);
-		}
+		SET_ZERROR_ERROR("inflate: inflating the group entry dictionary", ret);
 		goto ret;
 	}
 
@@ -626,14 +649,7 @@ static bool cc4group_uncompressGroup(CC4Group* const this, CC4Group_ReadCallback
 
 	if(!cc4group_inflateFillOutput(&strm, readCallback, callbackArg, memoryManagement, &eof, &readData, &ret))
 	{
-		if(eof && ret == Z_BUF_ERROR)
-		{
-			SET_EOD_ERROR("inflating the group contents");
-		}
-		else
-		{
-			SET_ZERROR_ERROR("inflate: inflating the group contents", ret);
-		}
+		SET_ZERROR_ERROR("inflate: inflating the group contents", ret);
 		goto ret;
 	}