Parse expressions in a separate function

This commit is contained in:
Jeffrey Pfau 2014-07-12 14:50:09 -07:00
parent f74815988b
commit f71edb1684
1 changed files with 43 additions and 24 deletions

View File

@ -295,46 +295,46 @@ enum Operation {
DIVIDE
};
static uint32_t _performOperation(enum Operation operation, uint32_t current, uint32_t next) {
static void _performOperation(enum Operation operation, uint32_t next, struct DebugVector* dv) {
switch (operation) {
case ASSIGN:
current = next;
dv->intValue = next;
break;
case ADD:
current += next;
dv->intValue += next;
break;
case SUBTRACT:
current -= next;
dv->intValue -= next;
break;
case MULTIPLY:
current *= next;
dv->intValue *= next;
break;
case DIVIDE:
if (next != 0) {
current /= next;
dv->intValue /= next;
} else {
return 0;
dv->type = ERROR_TYPE;
return;
}
break;
}
return current;
}
static struct DebugVector* _DVParse(struct CLIDebugger* debugger, const char* string, size_t length) {
static size_t _parseExpression(struct CLIDebugger* debugger, const char* string, size_t length, struct DebugVector* dv) {
if (!string || length < 1) {
return 0;
}
enum _DVParseState state = PARSE_ROOT;
struct DebugVector dvTemp = { .type = INT_TYPE };
uint32_t current = 0;
uint32_t next = 0;
size_t adjusted = 0;
enum _DVParseState state = PARSE_ROOT;
enum Operation operation = ASSIGN;
while (length > 0 && string[0] && string[0] != ' ' && state != PARSE_ERROR) {
char token = string[0];
++string;
++adjusted;
--length;
switch (state) {
case PARSE_ROOT:
@ -463,25 +463,25 @@ static struct DebugVector* _DVParse(struct CLIDebugger* debugger, const char* st
next += token - '0';
break;
case '+':
current = _performOperation(operation, current, next);
_performOperation(operation, next, dv);
next = 0;
state = PARSE_ROOT;
operation = ADD;
break;
case '-':
current = _performOperation(operation, current, next);
_performOperation(operation, next, dv);
next = 0;
state = PARSE_ROOT;
operation = SUBTRACT;
break;
case '*':
current = _performOperation(operation, current, next);
_performOperation(operation, next, dv);
next = 0;
state = PARSE_ROOT;
operation = MULTIPLY;
break;
case '/':
current = _performOperation(operation, current, next);
_performOperation(operation, next, dv);
next = 0;
state = PARSE_ROOT;
operation = DIVIDE;
@ -527,25 +527,25 @@ static struct DebugVector* _DVParse(struct CLIDebugger* debugger, const char* st
next += token - 'a' + 10;
break;
case '+':
current = _performOperation(operation, current, next);
_performOperation(operation, next, dv);
next = 0;
state = PARSE_ROOT;
operation = ADD;
break;
case '-':
current = _performOperation(operation, current, next);
_performOperation(operation, next, dv);
next = 0;
state = PARSE_ROOT;
operation = SUBTRACT;
break;
case '*':
current = _performOperation(operation, current, next);
_performOperation(operation, next, dv);
next = 0;
state = PARSE_ROOT;
operation = MULTIPLY;
break;
case '/':
current = _performOperation(operation, current, next);
_performOperation(operation, next, dv);
next = 0;
state = PARSE_ROOT;
operation = DIVIDE;
@ -568,7 +568,7 @@ static struct DebugVector* _DVParse(struct CLIDebugger* debugger, const char* st
}
break;
case PARSE_EXPECT_SUFFIX:
current = _performOperation(operation, current, next);
_performOperation(operation, next, dv);
next = 0;
state = PARSE_ROOT;
switch (token) {
@ -595,14 +595,33 @@ static struct DebugVector* _DVParse(struct CLIDebugger* debugger, const char* st
}
}
current = _performOperation(operation, current, next);
if (state == PARSE_ERROR) {
dv->type = ERROR_TYPE;
} else {
_performOperation(operation, next, dv);
}
return adjusted;
}
static struct DebugVector* _DVParse(struct CLIDebugger* debugger, const char* string, size_t length) {
if (!string || length < 1) {
return 0;
}
struct DebugVector dvTemp = { .type = INT_TYPE };
size_t adjusted = _parseExpression(debugger, string, length, &dvTemp);
if (adjusted > length) {
dvTemp.type = ERROR_TYPE;
}
length -= adjusted;
string += adjusted;
struct DebugVector* dv = malloc(sizeof(struct DebugVector));
if (state == PARSE_ERROR || state == PARSE_ROOT) {
if (dvTemp.type == ERROR_TYPE) {
dv->type = ERROR_TYPE;
dv->next = 0;
} else {
dvTemp.intValue = current;
*dv = dvTemp;
if (string[0] == ' ') {
dv->next = _DVParse(debugger, string + 1, length - 1);