* Moved strace source into separate subdirectory.

* Now syscall names and parameters are printed. const char* parameters
  and return values are retrieved from the client and printed as string.
* Missing are still color output (does consoled support that?) and
  searching for given commands in the PATH. Nothing besides the standard
  mode has been tested yet, so it's probably not working.


git-svn-id: file:///srv/svn/repos/haiku/trunk/current@11345 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/apps/bin/strace/MemoryReader.cpp

@@ -0,0 +1,105 @@
+/*
+ * Copyright 2005, Ingo Weinhold, [email protected].
+ * Distributed under the terms of the MIT License.
+ */
+
+#include <stdio.h>
+#include <string.h>
+
+#include <debugger.h>
+
+#include "MemoryReader.h"
+
+// constructor
+MemoryReader::MemoryReader(port_id nubPort)
+	: fNubPort(nubPort),
+	  fReplyPort(-1)
+{
+	fReplyPort = create_port(1, "memory reader reply");
+	if (fReplyPort < 0) {
+		fprintf(stderr, "Failed to create memory reader reply port: %s\n",
+			strerror(fReplyPort));
+		exit(1);
+	}
+}
+
+// constructor
+MemoryReader::~MemoryReader()
+{
+	if (fReplyPort >= 0)
+		delete_port(fReplyPort);
+}
+
+// Read
+status_t
+MemoryReader::Read(void *_address, void *_buffer, int32 size, int32 &bytesRead)
+{
+	char *address = (char*)_address;
+	char *buffer = (char*)_buffer;
+	bytesRead = 0;
+
+	// If the region to be read crosses page boundaries, we split it up into
+	// smaller chunks.
+	while (size > 0) {
+		int32 toRead = size;
+		if (toRead > B_MAX_READ_WRITE_MEMORY_SIZE)
+			toRead = B_MAX_READ_WRITE_MEMORY_SIZE;
+		if ((uint32)address % B_PAGE_SIZE + toRead > B_PAGE_SIZE)
+			toRead = B_PAGE_SIZE - (uint32)address % B_PAGE_SIZE;
+
+		status_t error = _Read(address, buffer, toRead);
+
+		// If reading fails, we only fail, if we haven't read something yet.
+		if (error != B_OK) {
+			if (bytesRead > 0)
+				return B_OK;
+			return error;
+		}
+
+		bytesRead += toRead;
+		address += toRead;
+		buffer += toRead;
+		size -= toRead;
+	}
+
+	return B_OK;
+}
+
+// _Read
+status_t
+MemoryReader::_Read(void *address, void *buffer, int32 size)
+{
+	// prepare message
+	debug_nub_read_memory message;
+	message.reply_port = fReplyPort;
+	message.address = address;
+	message.size = size;
+
+	// send message
+	while (true) {
+		status_t error = write_port(fNubPort, B_DEBUG_MESSAGE_READ_MEMORY,
+			&message, sizeof(message));
+		if (error == B_OK)
+			break;
+		if (error != B_INTERRUPTED)
+			return error;
+	}
+
+	// get reply
+	int32 code;
+	debug_nub_read_memory_reply reply;
+	while (true) {
+		ssize_t bytesRead = read_port(fReplyPort, &code, &reply, sizeof(reply));
+		if (bytesRead > 0)
+			break;
+		if (bytesRead != B_INTERRUPTED)
+			return bytesRead;
+	}
+
+	if (reply.error != B_OK)
+		return reply.error;
+
+	memcpy(buffer, reply.data, size);
+
+	return B_OK;
+}