From 329a03a324b8515338db6b03912b9e167a66de37 Mon Sep 17 00:00:00 2001
From: deuce <>
Date: Tue, 23 Oct 2012 05:06:43 +0000
Subject: [PATCH] Make the debugger actually useful. Added backtrace (bt) and
up/down commands. Allow specifying breakpoints in file:line format for future
load()s.
Breakpoints are a small memory leak right now as there's no way to clear them.
---
src/sbbs3/jsexec.c | 321 ++++++++++++++++++++++++++++++++++++++-------
1 file changed, 274 insertions(+), 47 deletions(-)
diff --git a/src/sbbs3/jsexec.c b/src/sbbs3/jsexec.c
index 4583a72bb3..251a4c49d1 100644
--- a/src/sbbs3/jsexec.c
+++ b/src/sbbs3/jsexec.c
@@ -82,13 +82,6 @@ BOOL daemonize=FALSE;
#endif
char orig_cwd[MAX_PATH+1];
BOOL debugger=FALSE;
-enum debug_action {
- DEBUG_CONTINUE,
- DEBUG_EXIT
-};
-
-static JSTrapStatus trap_handler(JSContext *cx, JSScript *script, jsbytecode *pc, jsval *rval, jsval closure);
-static enum debug_action debug_prompt(JSScript *script);
void banner(FILE* fp)
{
@@ -776,35 +769,203 @@ static const char* js_ext(const char* fname)
* This doesn't belong here and is done wrong...
* mcmlxxix should love it.
*/
-static enum debug_action debug_prompt(JSScript *script)
+#include <link_list.h>
+link_list_t breakpoints;
+link_list_t scripts;
+enum debug_action {
+ DEBUG_CONTINUE,
+ DEBUG_EXIT
+};
+static JSTrapStatus trap_handler(JSContext *cx, JSScript *script, jsbytecode *pc, jsval *rval, jsval closure);
+static JSTrapStatus throw_handler(JSContext *cx, JSScript *script, jsbytecode *pc, jsval *rval, void *closure);
+static enum debug_action debug_prompt(JSContext *cx, JSScript *script);
+
+struct breakpoint {
+ uintN line;
+ char name[];
+};
+
+struct cur_script {
+ JSScript *script;
+ char *fname;
+ uintN firstline;
+ uintN lastline;
+};
+
+static void newscript_handler(JSContext *cx,
+ const char *filename, /* URL of script */
+ uintN lineno, /* first line */
+ JSScript *script,
+ JSFunction *fun,
+ void *callerdata)
{
- char line[1024];
+ const char *fname=NULL;
+ struct cur_script *cs;
+ list_node_t *node;
+ struct breakpoint *bp;
+ jsbytecode *pc;
+
+ cs=(struct cur_script *)malloc(sizeof(struct cur_script));
+ if(!cs) {
+ fputs("Error allocated script struct", stderr);
+ return;
+ }
+ fname=JS_GetScriptFilename(cx, script);
+ cs->fname=strdup(fname);
+ if(cs->fname)
+ fname=getfname(fname);
+ cs->firstline=lineno;
+ cs->lastline=lineno+JS_GetScriptLineExtent(cx, script);
+ cs->script=script;
+
+ // Loop through breakpoints.
+ for(node=listFirstNode(&breakpoints); node; node=listNextNode(node)) {
+ bp=(struct breakpoint *)node->data;
+ if(strcmp(fname, bp->name)==0 || strcmp(cs->fname, bp->name)==0) {
+ if(bp->line >= cs->firstline && bp->line <= cs->lastline) {
+ pc=JS_LineNumberToPC(cx, script, bp->line);
+ if(pc==NULL) {
+ fprintf(stderr, "NEWSCRIPT: Unable to locate line %u\n", bp->line);
+ break;
+ }
+ if(JS_PCToLineNumber(cx, script, pc)!=bp->line) {
+ continue;
+ }
+ if(!JS_SetTrap(cx, script, pc, trap_handler, JSVAL_VOID)) {
+ fprintf(stderr, "NEWSCRIPT: Unable to set breakpoint at line %u\n",bp->line);
+ }
+ }
+ }
+ }
+ listPushNode(&scripts, cs);
+}
+static void killscript_handler(JSContext *cx, JSScript *script, void *callerdata)
+{
+ list_node_t *node;
+ list_node_t *pnode;
+ struct cur_script *cs;
+
+ for(node=listFirstNode(&scripts); node; node=listNextNode(node)) {
+ cs=(struct cur_script *)node->data;
+
+ if(cs->script == script) {
+ pnode=listPrevNode(node);
+ free(cs->fname);
+ listRemoveNode(&scripts, node, TRUE);
+ }
+ }
+}
+
+static void init_debugger(JSRuntime *rt, JSContext *cx)
+{
+ JS_SetDebugMode(cx, JS_TRUE);
+ JS_SetThrowHook(js_runtime, throw_handler, NULL);
+ listInit(&breakpoints,LINK_LIST_MUTEX);
+ listInit(&scripts,LINK_LIST_MUTEX);
+ JS_SetNewScriptHook(rt, newscript_handler, NULL);
+ JS_SetDestroyScriptHook(rt, killscript_handler, NULL);
+}
+
+static enum debug_action debug_prompt(JSContext *cx, JSScript *script)
+{
+ char line[1024];
+ const char *fpath;
+ const char *fname;
+ JSStackFrame *fp;
+ JSFunction *fn;
+ jsbytecode *pc;
+ char *cp;
+ jsrefcount rc;
+
+ fp=JS_GetScriptedCaller(cx, NULL);
while(1) {
- if(JS_IsExceptionPending(js_cx))
+ if(JS_IsExceptionPending(cx))
fputs("!", stdout);
- fputs("JS> ", stdout);
+ fpath=JS_GetScriptFilename(cx, script);
+ if(fpath) {
+ fname=getfname(fpath);
+ fputs(fname, stdout);
+ if(fp) {
+ pc=JS_GetFramePC(cx, fp);
+ if(pc)
+ fprintf(stdout, ":%u",JS_PCToLineNumber(cx, script, pc));
+ fn=JS_GetFrameFunction(cx, fp);
+ if(fn) {
+ JSString *name;
+
+ name=JS_GetFunctionId(fn);
+ if(name) {
+ JSSTRING_TO_STRING(cx, name, cp, NULL);
+ fprintf(stdout, " %s()", cp);
+ }
+ }
+ }
+ }
+ fputs("> ", stdout);
+ rc=JS_SUSPENDREQUEST(cx);
if(fgets(line, sizeof(line), stdin)==NULL) {
fputs("Error readin input\n",stderr);
+ JS_RESUMEREQUEST(cx, rc);
continue;
}
+ JS_RESUMEREQUEST(cx, rc);
if(strncmp(line, "break ", 6)==0) {
- ulong linenum=strtoul(line+6, NULL, 10);
- jsbytecode *pc;
-
+ ulong linenum=0;
+ jsbytecode *pc;
+ const char *sname;
+ struct cur_script *cs;
+ list_node_t *node;
+ struct breakpoint *bp;
+ const char *text;
+ char *num;
+
+ text=line+6;
+ if(isdigit(*text) && strchr(text,'.')==NULL) {
+ linenum=strtoul(text, NULL, 10);
+ text=fpath;
+ }
+ else {
+ num=strchr(text,':');
+ if(num) {
+ *num=0;
+ num++;
+ if(!(isdigit(*num))) {
+ fputs("Unable to parse breakpoint\n",stderr);
+ continue;
+ }
+ linenum=strtoul(num, NULL, 10);
+ }
+ }
if(linenum==ULONG_MAX) {
fputs("Unable to parse line number\n",stderr);
continue;
}
- pc=JS_LineNumberToPC(js_cx, script, linenum);
- if(pc==NULL) {
- fprintf(stderr, "Unable to locate line %lu\n", linenum);
- break;
+ for(node=listFirstNode(&scripts); node; node=listNextNode(node)) {
+ cs=(struct cur_script *)node->data;
+ sname=getfname(cs->fname);
+ if(strcmp(sname, text)==0 || strcmp(cs->fname, text)==0) {
+ pc=JS_LineNumberToPC(cx, cs->script, linenum);
+ if(JS_PCToLineNumber(cx, cs->script, pc)!=linenum)
+ continue;
+ if(pc==NULL) {
+ fprintf(stderr, "Unable to locate line %lu\n", linenum);
+ continue;
+ }
+ if(!JS_SetTrap(cx, cs->script, pc, trap_handler, JSVAL_VOID)) {
+ fprintf(stderr, "Unable to set breakpoint at line %lu\n",linenum);
+ }
+ }
}
- if(!JS_SetTrap(js_cx, script, pc, trap_handler, JSVAL_VOID)) {
- fprintf(stderr, "Unable to set breakpoint at line %lu\n",linenum);
+ bp=(struct breakpoint *)malloc(sizeof(uintN)+strlen(text)+1);
+ if(!bp) {
+ fputs("Unable to allocate breakpoint\n",stderr);
+ continue;
}
+ bp->line=linenum;
+ strcpy(bp->name, text);
+ listPushNode(&breakpoints, bp);
continue;
}
if(strncmp(line, "r", 1)==0) {
@@ -814,50 +975,118 @@ static enum debug_action debug_prompt(JSScript *script)
strncmp(line, "e ", 2)==0
) {
jsval ret;
- JSStackFrame *fp;
jsval oldexcept;
BOOL has_old=FALSE;
int cmdlen=5;
if(line[1]==' ')
cmdlen=2;
- if(JS_IsExceptionPending(js_cx)) {
- if(JS_GetPendingException(js_cx, &oldexcept))
+ if(JS_IsExceptionPending(cx)) {
+ if(JS_GetPendingException(cx, &oldexcept))
has_old=TRUE;
- JS_ClearPendingException(js_cx);
+ JS_ClearPendingException(cx);
}
- fp=JS_GetScriptedCaller(js_cx, NULL);
if(!fp) {
if(has_old)
- JS_SetPendingException(js_cx, oldexcept);
+ JS_SetPendingException(cx, oldexcept);
fputs("Unable to get frame pointer\n", stderr);
continue;
}
- if(!JS_EvaluateInStackFrame(js_cx, fp, line+cmdlen, strlen(line)-cmdlen, "eval-d statement", 1, &ret)) {
- if(JS_IsExceptionPending(js_cx)) {
- JS_SetErrorReporter(js_cx, js_ErrorReporter);
- JS_ReportPendingException(js_cx);
- JS_ClearPendingException(js_cx);
+ if(!JS_EvaluateInStackFrame(cx, fp, line+cmdlen, strlen(line)-cmdlen, "eval-d statement", 1, &ret)) {
+ if(JS_IsExceptionPending(cx)) {
+ JS_SetErrorReporter(cx, js_ErrorReporter);
+ JS_ReportPendingException(cx);
+ JS_ClearPendingException(cx);
}
}
else {
// TODO: Check ret...
}
if(has_old)
- JS_SetPendingException(js_cx, oldexcept);
+ JS_SetPendingException(cx, oldexcept);
continue;
}
if(strncmp(line, "clear", 5)==0) {
- JS_ClearPendingException(js_cx);
+ JS_ClearPendingException(cx);
+ continue;
+ }
+ if(strncmp(line, "bt", 2)==0
+ || strncmp(line, "backtrace", 9)==0) {
+ JSScript *fs;
+ JSStackFrame *fpi=NULL;
+ int fnum=0;
+
+ while(JS_FrameIterator(cx, &fpi)) {
+ fs=JS_GetFrameScript(cx, fpi);
+ fname=JS_GetScriptFilename(cx, fs);
+ if(fname==NULL)
+ fname="No name";
+ fname=getfname(fname);
+ pc=JS_GetFramePC(cx, fpi);
+ fprintf(stdout, "%c#%-2u %p ",fpi==fp?'*':' ',fnum,pc);
+ fn=JS_GetFrameFunction(cx, fpi);
+ if(fn) {
+ JSString *name;
+
+ name=JS_GetFunctionId(fn);
+ if(name) {
+ JSSTRING_TO_STRING(cx, name, cp, NULL);
+ fprintf(stdout, "in %s() ", cp);
+ }
+ }
+ fputs("at ",stdout);
+ fputs(fname, stdout);
+ if(pc)
+ fprintf(stdout, ":%u",JS_PCToLineNumber(cx, fs, pc));
+ fputs("\n", stdout);
+ fnum++;
+ }
+ continue;
+ }
+ if(strncmp(line,"up", 2)==0) {
+ JSStackFrame *fpn=fp;
+
+ JS_FrameIterator(cx, &fpn);
+ if(fpn==NULL) {
+ fputs("No frame above this one...\n",stderr);
+ continue;
+ }
+ fp=fpn;
+ script=JS_GetFrameScript(cx, fp);
+ continue;
+ }
+ if(strncmp(line,"down", 4)==0) {
+ JSStackFrame *fpi=NULL;
+ JSStackFrame *fpp=NULL;
+
+ while(JS_FrameIterator(cx, &fpi)) {
+ if(fpi==fp) {
+ if(fpp==NULL) {
+ fputs("Already at deepest stack frame\n",stderr);
+ break;
+ }
+ fp=fpp;
+ script=JS_GetFrameScript(cx, fp);
+ break;
+ }
+ fpp=fpi;
+ }
+ if(fpi==NULL)
+ fputs("A strange amd mysterious error occured!\n",stderr);
continue;
}
fputs("Unrecognized command:\n"
- "break #### - Sets a breakpoint\n"
- "r - Runs the script\n"
- "eval <statement> - eval() <statement> in the current frame\n"
- "e <statement> - eval() <statement> in the current frame\n"
- "clear - Clears pending exceptions (doesn't seem to help)\n"
+ "break [file:]#### - Sets a breakpoint at line #### in file\n"
+ " If no file is specified, uses the current one\n"
+ "r - Runs the script\n"
+ "eval <statement> - eval() <statement> in the current frame\n"
+ "e <statement> - eval() <statement> in the current frame\n"
+ "clear - Clears pending exceptions (doesn't seem to help)\n"
+ "bt - Prints a backtrace\n"
+ "backtrace - Alias for bt\n"
+ "up - Move to the previous stack frame\n"
+ "down - Move to the next stack frame\n"
"\n",stderr);
}
return DEBUG_CONTINUE;
@@ -869,7 +1098,7 @@ static JSTrapStatus trap_handler(JSContext *cx, JSScript *script, jsbytecode *pc
fputs("Breakpoint reached\n",stdout);
- switch(debug_prompt(script)) {
+ switch(debug_prompt(cx, script)) {
case DEBUG_CONTINUE:
return JSTRAP_CONTINUE;
case DEBUG_EXIT:
@@ -884,7 +1113,7 @@ static JSTrapStatus throw_handler(JSContext *cx, JSScript *script, jsbytecode *p
fputs("Exception thrown\n",stdout);
- switch(debug_prompt(script)) {
+ switch(debug_prompt(cx, script)) {
case DEBUG_CONTINUE:
return JSTRAP_CONTINUE;
case DEBUG_EXIT:
@@ -1003,6 +1232,8 @@ long js_exec(const char *fname, char** args)
fclose(fp);
start=xp_timer();
+ if(debugger)
+ init_debugger(js_runtime, js_cx);
if((js_script=JS_CompileScript(js_cx, js_glob, js_buf, js_buflen, fname==NULL ? NULL : path, 1))==NULL) {
lprintf(LOG_ERR,"!Error compiling script from %s",path);
return(-1);
@@ -1014,11 +1245,9 @@ long js_exec(const char *fname, char** args)
js_PrepareToExecute(js_cx, js_glob, fname==NULL ? NULL : path, orig_cwd);
start=xp_timer();
- if((!debugger) || debug_prompt(JS_GetScriptFromObject(js_script))==DEBUG_CONTINUE) {
- if(debugger)
- JS_SetThrowHook(js_runtime, throw_handler, NULL);
- JS_ExecuteScript(js_cx, js_glob, js_script, &rval);
- }
+ if(debugger)
+ debug_prompt(js_cx, JS_GetScriptFromObject(js_script));
+ JS_ExecuteScript(js_cx, js_glob, js_script, &rval);
JS_GetProperty(js_cx, js_glob, "exit_code", &rval);
if(rval!=JSVAL_VOID && JSVAL_IS_NUMBER(rval)) {
char *p;
@@ -1319,8 +1548,6 @@ int main(int argc, char **argv, char** environ)
}
fprintf(statfp,"\n");
- if(debugger)
- JS_SetDebugMode(js_cx, JS_TRUE);
result=js_exec(module,&argv[argn]);
JS_RemoveObjectRoot(js_cx, &js_glob);
JS_ENDREQUEST(js_cx);
--
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