* Register command with add_debugger_command_etc() and show some nicer

usage text.
* Removed "length" parameter from disasm_arch_dump_insns() and the
  instruction count limit. If at all this should be an architecture
  implementation specific limitation.
* In the x86 case we use an input hook instead of a fixed buffer, now.
* Addressed TODO: If no address is given, the current iframe's PC is
  used.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@27187 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/add-ons/kernel/debugger/disasm/disasm.cpp

@@ -3,32 +3,48 @@
  * Distributed under the terms of the MIT License.
  */
 
+#include <arch/debug.h>
 #include <debug.h>
 #include <signal.h>
 
 #include "disasm_arch.h"
 
+
 int
 disasm_command(int argc, char **argv)
 {
-	uint64 pc;
-	size_t count = 10;
-
-	if (argc < 2) {
-		kprintf("Usage: dis addr [count]\n");
-		return 1;
+	if (argc > 3) {
+		print_debugger_command_usage(argv[0]);
+		return 0;
+	}
+
+	// get PC
+	uint64 pc;
+	if (argc >= 2) {
+		if (!evaluate_debug_expression(argv[1], &pc, false))
+			return 0;
+	} else {
+		pc = (addr_t)arch_debug_get_interrupt_pc();
+		if (pc == 0) {
+			kprintf("Failed to get current PC!\n");
+			return 0;
+		}
+	}
+
+	// get count
+	uint64 count = 10;
+	if (argc >= 3) {
+		if (!evaluate_debug_expression(argv[2], &count, false))
+			return 0;
 	}
 
-	// TODO: use iframe pc by default
 	// TODO: autoincrement
-	pc = parse_expression(argv[1]);
-	if (argc > 2)
-		count = (size_t)parse_expression(argv[2]);
-	count = MIN(count, 50);
-	disasm_arch_dump_insns((addr_t)pc, 200, count);
+
+	disasm_arch_dump_insns((addr_t)pc, count);
 	return 0;
 }
 
+
 static status_t
 std_ops(int32 op, ...)
 {
@@ -38,7 +54,13 @@ std_ops(int32 op, ...)
 		err = disasm_arch_init();
 		if (err < 0)
 			return err;
-		return add_debugger_command("dis", disasm_command, "output disassembly at address");
+		return add_debugger_command_etc("dis", disasm_command,
+			"Print disassembly at address",
+			"[ <address>  [ <count> ] ]\n"
+			"Prints disassembly at address.\n"
+			"  <address>   - Address at which to start disassembling\n"
+			"                (defaults to current PC).\n"
+			"  <count>     - Number of instructions to disassemble.\n", 0);
 	} else if (op == B_MODULE_UNINIT) {
 		remove_debugger_command("dis", disasm_command);
 		return disasm_arch_fini();
@@ -61,7 +83,7 @@ static struct debugger_module_info sModuleInfo = {
 	NULL
 };
 
-module_info *modules[] = { 
+module_info *modules[] = {
 	(module_info *)&sModuleInfo,
 	NULL
 };

src/add-ons/kernel/debugger/disasm/disasm_arch.h

@@ -12,7 +12,7 @@ extern "C" {
 extern status_t disasm_arch_init();
 extern status_t disasm_arch_fini();
 
-extern status_t disasm_arch_dump_insns(addr_t where, size_t length, int count);
+extern status_t disasm_arch_dump_insns(addr_t where, int count);
 
 #ifdef __cplusplus
 }

src/add-ons/kernel/debugger/disasm/m68k/disasm_arch.cpp

@@ -8,7 +8,7 @@
 #include "disasm_arch.h"
 
 status_t
-disasm_arch_dump_insns(addr_t where, size_t length, int count)
+disasm_arch_dump_insns(addr_t where, int count)
 {
 	return ENOENT;
 }

src/add-ons/kernel/debugger/disasm/ppc/disasm_arch.cpp

@@ -8,7 +8,7 @@
 #include "disasm_arch.h"
 
 status_t
-disasm_arch_dump_insns(addr_t where, size_t length, int count)
+disasm_arch_dump_insns(addr_t where, int count)
 {
 	return ENOENT;
 }

src/add-ons/kernel/debugger/disasm/x86/disasm_arch.cpp

@@ -10,9 +10,25 @@
 #include "udis86.h"
 
 static ud_t sUDState;
+static addr_t sCurrentReadAddress;
 static void (*sSyntax)(ud_t *) = UD_SYN_ATT;
 static unsigned int sVendor = UD_VENDOR_INTEL;
 
+
+static int
+read_next_byte(struct ud*)
+{
+	uint8_t buffer;
+	if (user_memcpy(&buffer, (void*)sCurrentReadAddress, 1) != B_OK) {
+		kprintf("<read fault>\n");
+		return UD_EOI;
+	}
+
+	sCurrentReadAddress++;
+	return buffer;
+}
+
+
 extern "C" void
 disasm_arch_assert(const char *condition)
 {
@@ -21,12 +37,13 @@ disasm_arch_assert(const char *condition)
 
 
 status_t
-disasm_arch_dump_insns(addr_t where, size_t length, int count)
+disasm_arch_dump_insns(addr_t where, int count)
 {
 	//status_t err;
 	int i;
-	
-	ud_set_input_buffer(&sUDState, (unsigned char *)where, length);
+
+	ud_set_input_hook(&sUDState, &read_next_byte);
+	sCurrentReadAddress	= where;
 	ud_set_mode(&sUDState, 32);
 	ud_set_pc(&sUDState, (uint64_t)where);
 	ud_set_syntax(&sUDState, sSyntax);
@@ -37,7 +54,7 @@ disasm_arch_dump_insns(addr_t where, size_t length, int count)
 		if (ret < 1)
 			break;
 		// TODO: dig operands and lookup symbols
-		kprintf("0x%08lx: %16.16s\t%s\n", 
+		kprintf("0x%08lx: %16.16s\t%s\n",
 			(uint32)(/*where +*/ ud_insn_off(&sUDState)),
 			ud_insn_hex(&sUDState),
 			ud_insn_asm(&sUDState));