Fixed horrendous crash in the JIT from packing change in the debug table (bug 3334, r=me).

I accidentally changed the debug table packing in a commit a while ago.  This explains the nonsense debug output and crashes people have been getting on the 1.1 branch.  Fortunately this is (mostly) detectable via the "debug.natives" table and the JIT will unpack symbols based on that information.

public/sourcepawn/sp_file_headers.h

@@ -57,7 +57,7 @@
 #endif
 
 #define SPFILE_MAGIC	0x53504646		/**< Source Pawn File Format (SPFF) */
-#define SPFILE_VERSION	0x0101			/**< Uncompressed bytecode */
+#define SPFILE_VERSION	0x0102			/**< File format version */
 
 //:TODO: better compiler/nix support
 #if defined __linux__
@@ -266,4 +266,40 @@ typedef struct fp_fdbg_ntvarg_s
 #pragma pack(pop) /* reset previous packing */
 #endif
 
+/**
+ * Okay, my mistake here.  I apologize.  I changed the packing by accident and there is no 
+ * version bump aside from the presence of the native debug table.  Cat's out of the bag 
+ * for SourceMod and we have no choice but to shim compat for the old version.  For people 
+ * parsing plugins on their own, use the presence of the native debug table to decide this.  
+ * If there are no natives (really, there is a very very low chance of this), heuristics 
+ * might be necessary.  I've bumped the version to 0x0102 but there may have been plugins 
+ * in the 0x0101 window with no natives.
+ */
+
+/**
+ * @brief Unpacked file-encoded debug symbol array dimension info.
+ */
+typedef struct sp_u_fdbg_arraydim_s
+{
+	int16_t		tagid;		/**< Tag id */
+	uint32_t	size;		/**< Size of dimension */
+} sp_u_fdbg_arraydim_t;
+
+/**
+ * @brief Unpacked file-encoded debug symbol information.
+ */
+typedef struct sp_u_fdbg_symbol_s
+{
+	int32_t		addr;		/**< Address rel to DAT or stack frame */
+	int16_t		tagid;		/**< Tag id */
+	uint32_t	codestart;	/**< Start scope validity in code */
+	uint32_t	codeend;	/**< End scope validity in code */
+	uint8_t		ident;		/**< Variable type */
+	uint8_t		vclass;		/**< Scope class (local vs global) */
+	uint16_t	dimcount;	/**< Dimension count (for arrays) */
+	uint32_t	name;		/**< Offset into debug nametable */
+} sp_u_fdbg_symbol_t;
+
+
 #endif //_INCLUDE_SPFILE_HEADERS_H
+

sourcepawn/jit/BaseRuntime.cpp

@@ -69,6 +69,11 @@ int BaseRuntime::CreateFromMemory(sp_file_hdr_t *hdr, uint8_t *base)
 	plugin->base_size = hdr->imagesize;
 	set_err = SP_ERROR_NONE;
 
+	if (hdr->version == 0x0101)
+	{
+		plugin->debug.unpacked = true;
+	}
+
 	/* We have to read the name section first */
 	for (sectnum = 0; sectnum < hdr->sections; sectnum++)
 	{
@@ -195,6 +200,10 @@ int BaseRuntime::CreateFromMemory(sp_file_hdr_t *hdr, uint8_t *base)
 		{
 			plugin->debug.stringbase = (const char *)(base + secptr->dataoffs);
 		}
+		else if (strcmp(nameptr, ".dbg.natives") == 0)
+		{
+			plugin->debug.unpacked = false;
+		}
 
 		secptr++;
 		sectnum++;

sourcepawn/jit/engine2.cpp

@@ -88,7 +88,6 @@ IPluginRuntime *SourcePawnEngine2::LoadPlugin(ICompilation *co, const char *file
 		}
 	}
 
-
 	pRuntime = new BaseRuntime();
 	if ((error = pRuntime->CreateFromMemory(&hdr, base)) != SP_ERROR_NONE)
 	{

sourcepawn/jit/jit_shared.h

@@ -19,6 +19,7 @@ typedef struct sp_plugin_debug_s
 	sp_fdbg_line_t *lines;		/**< lines table */
 	uint32_t	syms_num;		/**< number of symbols */
 	sp_fdbg_symbol_t *symbols;	/**< symbol table */
+	bool unpacked;				/**< Whether debug structures are unpacked */
 } sp_plugin_debug_t;
 
 class BaseContext;

sourcepawn/jit/sp_vm_basecontext.cpp

@@ -742,37 +742,72 @@ int DebugInfo::LookupFile(ucell_t addr, const char **filename)
 
 int DebugInfo::LookupFunction(ucell_t addr, const char **name)
 {
-	uint32_t max, iter;
+	if (!m_pPlugin->debug.unpacked)
-	sp_fdbg_symbol_t *sym;
-	sp_fdbg_arraydim_t *arr;
-	uint8_t *cursor = (uint8_t *)(m_pPlugin->debug.symbols);
-
-	max = m_pPlugin->debug.syms_num;
-	for (iter = 0; iter < max; iter++)
 	{
-		sym = (sp_fdbg_symbol_t *)cursor;
+		uint32_t max, iter;
+		sp_fdbg_symbol_t *sym;
+		sp_fdbg_arraydim_t *arr;
+		uint8_t *cursor = (uint8_t *)(m_pPlugin->debug.symbols);
 
-		if (sym->ident == SP_SYM_FUNCTION
+		max = m_pPlugin->debug.syms_num;
-			&& sym->codestart <= addr 
+		for (iter = 0; iter < max; iter++)
-			&& sym->codeend > addr)
 		{
-			*name = m_pPlugin->debug.stringbase + sym->name;
+			sym = (sp_fdbg_symbol_t *)cursor;
-			return SP_ERROR_NONE;
+
-		}
+			if (sym->ident == SP_SYM_FUNCTION
+				&& sym->codestart <= addr 
+				&& sym->codeend > addr)
+			{
+				*name = m_pPlugin->debug.stringbase + sym->name;
+				return SP_ERROR_NONE;
+			}
+
+			if (sym->dimcount > 0)
+			{
+				cursor += sizeof(sp_fdbg_symbol_t);
+				arr = (sp_fdbg_arraydim_t *)cursor;
+				cursor += sizeof(sp_fdbg_arraydim_t) * sym->dimcount;
+				continue;
+			}
 
-		if (sym->dimcount > 0)
-		{
 			cursor += sizeof(sp_fdbg_symbol_t);
-			arr = (sp_fdbg_arraydim_t *)cursor;
-			cursor += sizeof(sp_fdbg_arraydim_t) * sym->dimcount;
-			continue;
 		}
 
-		cursor += sizeof(sp_fdbg_symbol_t);
+		return SP_ERROR_NOT_FOUND;
 	}
+	else
+	{
+		uint32_t max, iter;
+		sp_u_fdbg_symbol_t *sym;
+		sp_u_fdbg_arraydim_t *arr;
+		uint8_t *cursor = (uint8_t *)(m_pPlugin->debug.symbols);
 
-	return SP_ERROR_NOT_FOUND;
+		max = m_pPlugin->debug.syms_num;
+		for (iter = 0; iter < max; iter++)
+		{
+			sym = (sp_u_fdbg_symbol_t *)cursor;
 
+			if (sym->ident == SP_SYM_FUNCTION
+				&& sym->codestart <= addr 
+				&& sym->codeend > addr)
+			{
+				*name = m_pPlugin->debug.stringbase + sym->name;
+				return SP_ERROR_NONE;
+			}
+
+			if (sym->dimcount > 0)
+			{
+				cursor += sizeof(sp_u_fdbg_symbol_t);
+				arr = (sp_u_fdbg_arraydim_t *)cursor;
+				cursor += sizeof(sp_u_fdbg_arraydim_t) * sym->dimcount;
+				continue;
+			}
+
+			cursor += sizeof(sp_u_fdbg_symbol_t);
+		}
+
+		return SP_ERROR_NOT_FOUND;
+	}
 }
 
 int DebugInfo::LookupLine(ucell_t addr, uint32_t *line)

sourcepawn/jit/x86/jit_x86.cpp

@@ -1344,32 +1344,65 @@ void ProfCallGate_End(sp_context_t *ctx)
 
 const char *find_func_name(sp_plugin_t *plugin, uint32_t offs)
 {
-	uint32_t max, iter;
+	if (!plugin->debug.unpacked)
-	sp_fdbg_symbol_t *sym;
-	sp_fdbg_arraydim_t *arr;
-	uint8_t *cursor = (uint8_t *)(plugin->debug.symbols);
-
-	max = plugin->debug.syms_num;
-	for (iter = 0; iter < max; iter++)
 	{
-		sym = (sp_fdbg_symbol_t *)cursor;
+		uint32_t max, iter;
+		sp_fdbg_symbol_t *sym;
+		sp_fdbg_arraydim_t *arr;
+		uint8_t *cursor = (uint8_t *)(plugin->debug.symbols);
 
-		if (sym->ident == SP_SYM_FUNCTION
+		max = plugin->debug.syms_num;
-			&& sym->codestart <= offs 
+		for (iter = 0; iter < max; iter++)
-			&& sym->codeend > offs)
 		{
-			return plugin->debug.stringbase + sym->name;
+			sym = (sp_fdbg_symbol_t *)cursor;
-		}
+
+			if (sym->ident == SP_SYM_FUNCTION
+				&& sym->codestart <= offs 
+				&& sym->codeend > offs)
+			{
+				return plugin->debug.stringbase + sym->name;
+			}
+
+			if (sym->dimcount > 0)
+			{
+				cursor += sizeof(sp_fdbg_symbol_t);
+				arr = (sp_fdbg_arraydim_t *)cursor;
+				cursor += sizeof(sp_fdbg_arraydim_t) * sym->dimcount;
+				continue;
+			}
 
-		if (sym->dimcount > 0)
-		{
 			cursor += sizeof(sp_fdbg_symbol_t);
-			arr = (sp_fdbg_arraydim_t *)cursor;
-			cursor += sizeof(sp_fdbg_arraydim_t) * sym->dimcount;
-			continue;
 		}
+	}
+	else
+	{
+		uint32_t max, iter;
+		sp_u_fdbg_symbol_t *sym;
+		sp_u_fdbg_arraydim_t *arr;
+		uint8_t *cursor = (uint8_t *)(plugin->debug.symbols);
 
-		cursor += sizeof(sp_fdbg_symbol_t);
+		max = plugin->debug.syms_num;
+		for (iter = 0; iter < max; iter++)
+		{
+			sym = (sp_u_fdbg_symbol_t *)cursor;
+
+			if (sym->ident == SP_SYM_FUNCTION
+				&& sym->codestart <= offs 
+				&& sym->codeend > offs)
+			{
+				return plugin->debug.stringbase + sym->name;
+			}
+
+			if (sym->dimcount > 0)
+			{
+				cursor += sizeof(sp_u_fdbg_symbol_t);
+				arr = (sp_u_fdbg_arraydim_t *)cursor;
+				cursor += sizeof(sp_u_fdbg_arraydim_t) * sym->dimcount;
+				continue;
+			}
+
+			cursor += sizeof(sp_u_fdbg_symbol_t);
+		}
 	}
 
 	return NULL;