static struct_declaration *analyze_struct(parse_source *source) {
parse_token current = get_mandatory_token(source);
struct_declaration *dec = new(dec);
dec->name = current.data;
dec->members = ll_new();
current = get_mandatory_token(source);
if(current.data.data[0] != '{') {
semantic_error("Expected opening brace after name in struct declaration.", current.origin);
}
current = get_mandatory_token(source);
while(current.data.data[0] != '}') {
struct_member *member = new(member);
if(current.type != WORD) {
semantic_error("Struct members must be declared as <name> <type>;", current.origin);
}
member->name = current.data;
current = get_mandatory_token(source);
if(current.type != WORD) {
semantic_error("Struct members must be declared as <name> <type>;",current.origin);
}
member->type = current.data;
current = get_mandatory_token(source);
if(current.data.data[0] != ';') {
semantic_error("Struct members must be declared as <name> <type>;", current.origin);
}
ll_add_last(dec->members, member);
current = get_mandatory_token(source);
}
return dec;
}
void parse_line_range_desc(const char *arg, struct line_range *lr)
{
const char *ptr;
char *tmp;
/*
* <Syntax>
* SRC:SLN[+NUM|-ELN]
* FUNC[:SLN[+NUM|-ELN]]
*/
ptr = strchr(arg, ':');
if (ptr) {
lr->start = (unsigned int)strtoul(ptr + 1, &tmp, 0);
if (*tmp == '+')
lr->end = lr->start + (unsigned int)strtoul(tmp + 1,
&tmp, 0);
else if (*tmp == '-')
lr->end = (unsigned int)strtoul(tmp + 1, &tmp, 0);
else
lr->end = 0;
pr_debug("Line range is %u to %u\n", lr->start, lr->end);
if (lr->end && lr->start > lr->end)
semantic_error("Start line must be smaller"
" than end line.");
if (*tmp != '\0')
semantic_error("Tailing with invalid character '%d'.",
*tmp);
tmp = strndup(arg, (ptr - arg));
} else
tmp = strdup(arg);
if (strchr(tmp, '.'))
lr->file = tmp;
else
lr->function = tmp;
}
static func_declaration *analyze_func(parse_source *source) {
parse_token current = get_mandatory_token(source);
func_declaration *func = new(func);
func->parameters = ll_new();
if(current.type != WORD) {
semantic_error("Function declaration must be in the form func <name>(<parameters>) <returntype> {<block>}", current.origin);
}
func->name = current.data;
current = get_mandatory_token(source);
if(current.data.data[0] != '(') {
semantic_error("Function name must be followed by an open parenthesis", current.origin);
}
current = get_mandatory_token(source);
while(current.data.data[0] != ')') {
statement *name = new(name);
name->type = NAME;
name->children = ll_new();
if(current.type != WORD) {
printf("%s\n", evaluate(current.data));
semantic_error("Parameter names must be a valid identifier", current.origin);
}
name->data = current.data;
statement *param_type = parse_type_literal(source);
ll_add_first(name->children, param_type);
param_type->children = NULL;
ll_add_last(func->parameters, name);
current = get_mandatory_token(source);
if(current.data.data[0] == ',') {
current = get_mandatory_token(source);
}
}
statement *returnType = parse_type_literal(source);
func->type = returnType->data;
free(returnType);
current = peek_mandatory_token(source);
if(current.data.data[0] != '{') {
semantic_error("Function bodies must start with an open brace ('{')", current.origin);
}
int indent = 1;
get_mandatory_token(source);
func->root = new(func->root);
func->root->type = ROOT;
func->root->data = new_slice("");
func->root->children = ll_new();
while(indent > 0) {
statement *state = get_expression(source, &indent);
if(state != NULL)
ll_add_last(func->root->children, state);
}
return func;
}
/* Parse kprobe_events event into struct probe_point */
void parse_trace_kprobe_event(const char *str, struct probe_point *pp)
{
char pr;
char *p;
int ret, i, argc;
char **argv;
pr_debug("Parsing kprobe_events: %s\n", str);
argv = argv_split(str, &argc);
if (!argv)
die("argv_split failed.");
if (argc < 2)
semantic_error("Too less arguments.");
/* Scan event and group name. */
ret = sscanf(argv[0], "%c:%a[^/ \t]/%a[^ \t]",
&pr, (float *)(void *)&pp->group,
(float *)(void *)&pp->event);
if (ret != 3)
semantic_error("Failed to parse event name: %s", argv[0]);
pr_debug("Group:%s Event:%s probe:%c\n", pp->group, pp->event, pr);
pp->retprobe = (pr == 'r');
/* Scan function name and offset */
ret = sscanf(argv[1], "%a[^+]+%d", (float *)(void *)&pp->function,
&pp->offset);
if (ret == 1)
pp->offset = 0;
/* kprobe_events doesn't have this information */
pp->line = 0;
pp->file = NULL;
pp->nr_args = argc - 2;
pp->args = zalloc(sizeof(char *) * pp->nr_args);
for (i = 0; i < pp->nr_args; i++) {
p = strchr(argv[i + 2], '=');
if (p) /* We don't need which register is assigned. */
*p = '\0';
pp->args[i] = strdup(argv[i + 2]);
if (!pp->args[i])
die("Failed to copy argument.");
}
argv_free(argv);
}
static import_declaration *parse_import(parse_source *source) {
parse_token current = get_mandatory_token(source);
import_declaration *imp = new(imp);
imp->name = current.data;
current = get_mandatory_token(source);
if(!equals_string(current.data, ";")) {
semantic_error("Expected semicolon after import statement", current.origin);
}
return imp;
}
node_ptr
resolve_refs::visit (identifier &n)
{
if (std::find (refs.begin (), refs.end (), &n) != refs.end ())
throw semantic_error (refs, "variable `" + n.string + "' references itself (eventually)");
if (n.ref)
{
refs.push_back (&n);
resume (ref);
refs.pop_back ();
return n.ref;
}
return visitor::visit (n);
}
/* Parse perf-probe event definition */
void parse_perf_probe_event(const char *str, struct probe_point *pp,
bool *need_dwarf)
{
char **argv;
int argc, i;
*need_dwarf = false;
argv = argv_split(str, &argc);
if (!argv)
die("argv_split failed.");
if (argc > MAX_PROBE_ARGS + 1)
semantic_error("Too many arguments");
/* Parse probe point */
parse_perf_probe_probepoint(argv[0], pp);
if (pp->file || pp->line || pp->lazy_line)
*need_dwarf = true;
/* Copy arguments and ensure return probe has no C argument */
pp->nr_args = argc - 1;
pp->args = zalloc(sizeof(char *) * pp->nr_args);
for (i = 0; i < pp->nr_args; i++) {
pp->args[i] = strdup(argv[i + 1]);
if (!pp->args[i])
die("Failed to copy argument.");
if (is_c_varname(pp->args[i])) {
if (pp->retprobe)
semantic_error("You can't specify local"
" variable for kretprobe");
*need_dwarf = true;
}
}
argv_free(argv);
}
static statement *get_expression(parse_source *source, int *indent) {
parse_token token = get_mandatory_token(source);
if(equals_string(token.data, "{")) {
statement *expression = new(expression);
expression->type = BLOCK;
expression->children = ll_new();
expression->data = new_slice("");
int finished = *indent;
*indent += 1;
while(*indent != finished) {
statement *state = get_expression(source, indent);
if(state != NULL)
ll_add_last(expression->children, state);
}
return expression;
} else if(equals_string(token.data, "}")) {
*indent -= 1;
return NULL;
} else if(equals_string(token.data, "if") || equals_string(token.data, "while") || equals_string(token.data, "for")) {
statement *expression = new(expression);
if(equals_string(token.data, "if"))
expression->type = IF;
else if(equals_string(token.data, "while"))
expression->type = WHILE;
else if(equals_string(token.data, "for"))
expression->type = FOR;
expression->children = ll_new();
expression->data = new_slice("");
ll_add_last(expression->children, get_expression(source, indent)); //Add the header
if(expression->type == FOR) {
ll_add_last(expression->children, get_expression(source, indent)); //Add the header
ll_add_last(expression->children, get_expression(source, indent)); //Add the header
}
ll_add_last(expression->children, get_expression(source, indent)); //Add the body
if(expression->type == IF) {
parse_token next = peek_mandatory_token(source);
if(equals_string(next.data, "else")) {
get_mandatory_token(source);
statement *elseState = new(elseState);
elseState->type = ELSE;
elseState->children = ll_new();
elseState->data = new_slice("");
ll_add_last(expression->children, elseState);
ll_add_first(elseState->children, get_expression(source, indent));
}
}
return expression;
} else if(equals_string(token.data, "break") || equals_string(token.data, "continue")) {
statement *expression = new(expression);
expression->type = equals_string(token.data, "break") ? BREAK : CONTINUE;
expression->data = new_slice("");
expression->children = NULL;
parse_token next = get_mandatory_token(source);
if(!equals_string(next.data, ";"))
semantic_error("Expected a semicolon after a break or continue", next.origin);
return expression;
} else if(equals_string(token.data, "return")) {
statement *expression = new(expression);
expression->type = RETURN;
expression->data = new_slice("");
expression->children = ll_new();
ll_add_last(expression->children, get_expression(source, indent));
return expression;
} else {
linked_list *accumulator = ll_new();
parse_token next = token;
while(true) {
parse_token *allocated = new(allocated);
*allocated = token;
ll_add_last(accumulator, allocated);
next = peek_mandatory_token(source);
if(equals_string(next.data, "{") || equals_string(next.data, "}"))
break;
if(equals_string(next.data, ";")) {
get_mandatory_token(source);
break;
}
token = get_mandatory_token(source);
}
statement *expression = parse_simple_expression(accumulator);
ll_delete_all(accumulator);
return expression;
}
}
/* Parse probepoint definition. */
static void parse_perf_probe_probepoint(char *arg, struct probe_point *pp)
{
char *ptr, *tmp;
char c, nc = 0;
/*
* <Syntax>
* perf probe [EVENT=]SRC[:LN|;PTN]
* perf probe [EVENT=]FUNC[@SRC][+OFFS|%return|:LN|;PAT]
*
* TODO:Group name support
*/
ptr = strpbrk(arg, ";=@+%");
if (ptr && *ptr == '=') { /* Event name */
*ptr = '\0';
tmp = ptr + 1;
ptr = strchr(arg, ':');
if (ptr) /* Group name is not supported yet. */
semantic_error("Group name is not supported yet.");
if (!check_event_name(arg))
semantic_error("%s is bad for event name -it must "
"follow C symbol-naming rule.", arg);
pp->event = strdup(arg);
arg = tmp;
}
ptr = strpbrk(arg, ";:+@%");
if (ptr) {
nc = *ptr;
*ptr++ = '\0';
}
/* Check arg is function or file and copy it */
if (strchr(arg, '.')) /* File */
pp->file = strdup(arg);
else /* Function */
pp->function = strdup(arg);
DIE_IF(pp->file == NULL && pp->function == NULL);
/* Parse other options */
while (ptr) {
arg = ptr;
c = nc;
if (c == ';') { /* Lazy pattern must be the last part */
pp->lazy_line = strdup(arg);
break;
}
ptr = strpbrk(arg, ";:+@%");
if (ptr) {
nc = *ptr;
*ptr++ = '\0';
}
switch (c) {
case ':': /* Line number */
pp->line = strtoul(arg, &tmp, 0);
if (*tmp != '\0')
semantic_error("There is non-digit char"
" in line number.");
break;
case '+': /* Byte offset from a symbol */
pp->offset = strtoul(arg, &tmp, 0);
if (*tmp != '\0')
semantic_error("There is non-digit character"
" in offset.");
break;
case '@': /* File name */
if (pp->file)
semantic_error("SRC@SRC is not allowed.");
pp->file = strdup(arg);
DIE_IF(pp->file == NULL);
break;
case '%': /* Probe places */
if (strcmp(arg, "return") == 0) {
pp->retprobe = 1;
} else /* Others not supported yet */
semantic_error("%%%s is not supported.", arg);
break;
default:
DIE_IF("Program has a bug.");
break;
}
}
/* Exclusion check */
if (pp->lazy_line && pp->line)
semantic_error("Lazy pattern can't be used with line number.");
if (pp->lazy_line && pp->offset)
semantic_error("Lazy pattern can't be used with offset.");
if (pp->line && pp->offset)
semantic_error("Offset can't be used with line number.");
if (!pp->line && !pp->lazy_line && pp->file && !pp->function)
semantic_error("File always requires line number or "
"lazy pattern.");
if (pp->offset && !pp->function)
semantic_error("Offset requires an entry function.");
if (pp->retprobe && !pp->function)
semantic_error("Return probe requires an entry function.");
if ((pp->offset || pp->line || pp->lazy_line) && pp->retprobe)
semantic_error("Offset/Line/Lazy pattern can't be used with "
"return probe.");
pr_debug("symbol:%s file:%s line:%d offset:%d return:%d lazy:%s\n",
pp->function, pp->file, pp->line, pp->offset, pp->retprobe,
pp->lazy_line);
}
