Skip to content

convert Symbol & Token to linked list #7

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wants to merge 2 commits into
base: master
Choose a base branch
from
Open

convert Symbol & Token to linked list #7

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
e2a5529
change Symbol tabe to linked list
mzprog Jul 21, 2020
6e1ca92
change Token from array to linked list
mzprog Jul 22, 2020
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
115 changes: 86 additions & 29 deletions src/lexer.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -6,14 +6,18 @@
#include "tokens.h"

Token *getTokens(char *input) {
Token *tokArr = malloc(sizeof(Token) * MAX_TOKENS);
Token *tokHead = NULL; //malloc(sizeof(Token));
Token **tokPtr;// a var help to faster access
Token * tmp;

tokPtr= &tokHead;

char *token = malloc(sizeof(char) * MAX_TOK_LEN);
int i;
int slen = 0;
int tokenCount = 0;
//int tokenCount = 0;
int retType;



//If set, treat the input as code else it could be comment or string literal
int isCode = 1;
Expand All @@ -38,14 +42,19 @@ Token *getTokens(char *input) {
slen = 0;

retType = getType(token);
tmp = (Token *) malloc(sizeof(Token));
tmp->next = NULL;

if (retType == -1) {
tokArr[tokenCount].type = ID;
tmp->type = ID;
} else {
tokArr[tokenCount].type = retType;
tmp->type = retType;
}
tokArr[tokenCount].value = malloc(sizeof(char) * (strlen(token) + 1));
strcpy(tokArr[tokenCount].value, token);
tokenCount++;
tmp->value = malloc(sizeof(char) * (strlen(token) + 1));
strcpy(tmp->value, token);
*tokPtr = tmp;
tokPtr = &(*tokPtr)->next;

printf(" ");
strcpy(token, "");
break;
Expand All @@ -65,10 +74,17 @@ Token *getTokens(char *input) {
} else {
token[slen] = '\0';
slen = 0;
tokArr[tokenCount].type = NUM;
tokArr[tokenCount].value = malloc(sizeof(char) * (strlen(token) + 1));
strcpy(tokArr[tokenCount].value, token);
tokenCount++;

tmp = (Token *) malloc(sizeof(Token));
tmp->next = NULL;

tmp->type = NUM;
tmp->value = malloc(sizeof(char) * (strlen(token) + 1));
strcpy(tmp->value, token);

*tokPtr = tmp;
tokPtr = &(*tokPtr)->next;

printf(" ");
strcpy(token, "");
break;
Expand All @@ -88,11 +104,17 @@ Token *getTokens(char *input) {
literal[literalLen++] = input[i];
i++;
}

tmp = (Token *) malloc(sizeof(Token));
tmp->next = NULL;

literal[literalLen] = '\0';
tokArr[tokenCount].type = S_LITERAL;
tokArr[tokenCount].value = malloc(sizeof(char) * (strlen(literal) + 1));
strcpy(tokArr[tokenCount].value, literal);
tokenCount++;
tmp->type = S_LITERAL;
tmp->value = malloc(sizeof(char) * (strlen(literal) + 1));
strcpy(tmp->value, literal);

*tokPtr = tmp;
tokPtr = &(*tokPtr)->next;
}
// if (!isCode) {
// if (input[i] != '\\') {
Expand Down Expand Up @@ -122,24 +144,47 @@ Token *getTokens(char *input) {
} else {
token[slen] = '\0';
slen = 0;
findLongestToken(token, tokArr, &tokenCount);
tokPtr = findLongestToken(token, tokPtr);
break;
}
i++;
}
}
}
tokArr[tokenCount].type = ENTER;
tokArr[tokenCount].value = "CR";

tmp = (Token *) malloc(sizeof(Token));
tmp->next = NULL;

tmp->type = ENTER;
tmp->value = "CR";

*tokPtr = tmp;

free(token);
return tokArr;
return tokHead;
}

void freeTokens(Token *tok)
{
Token *tmp;

while(tok)
{
tmp = tok->next;
free(tok->value);
free(tok);

tok = tmp;
}
}

/**
* Method to find the longest valid token
* from the given longest special characters token
* tokCur is the last Token in the list, will help us to link the new nodes
**/
void findLongestToken(char *token, Token *tokArr, int *tokenCount) {
Token **findLongestToken(char *token, Token **tokPtr) {
Token *tmp;
char *temp = malloc(sizeof(char) * MAX_TOK_LEN);
char *longToken = malloc(sizeof(char) * MAX_TOK_LEN);
int i, m = 0;
Expand All @@ -153,10 +198,16 @@ void findLongestToken(char *token, Token *tokArr, int *tokenCount) {
} else {
// printf("%s ", longToken);
// printf("%d ", getType(longToken));
tokArr[*tokenCount].type = getType(longToken);
tokArr[*tokenCount].value = malloc(sizeof(char) * (strlen(longToken) + 1 ));
strcpy(tokArr[*tokenCount].value, longToken);
(*tokenCount)++;
tmp = (Token *) malloc(sizeof(Token));

tmp->next = NULL;
tmp->type = getType(longToken);
tmp->value = malloc(sizeof(char) * (strlen(longToken) + 1 ));
strcpy(tmp->value, longToken);

*tokPtr = tmp;
tokPtr = &(*tokPtr)->next;

m = 0;
//To consider the already considered character in the invalid token
i--;
Expand All @@ -166,13 +217,19 @@ void findLongestToken(char *token, Token *tokArr, int *tokenCount) {
// printf("%d ", getType(longToken));
if( m!=0 )
{
tokArr[*tokenCount].type = getType(longToken);
tokArr[*tokenCount].value = malloc(sizeof(char) * (strlen(longToken) + 1 ));
strcpy(tokArr[*tokenCount].value, longToken);
(*tokenCount)++;
tmp = (Token *) malloc(sizeof(Token));

tmp->next = NULL;
tmp->type = getType(longToken);
tmp->value = malloc(sizeof(char) * (strlen(longToken) + 1 ));
strcpy(tmp->value, longToken);
*tokPtr = tmp;
tokPtr = &(*tokPtr)->next;
}
free(longToken);
free(temp);

return tokPtr;
}

int isValidToken(char *token) {
Expand Down
4 changes: 3 additions & 1 deletion src/lexer.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -16,6 +16,7 @@
typedef struct Tokens{
int type;
char *value;
struct Tokens *next;
} Token;

typedef struct Directives{
Expand All @@ -33,8 +34,9 @@ typedef struct Directives{
Directive *directives(char *);
int getType(char *);
Token *getTokens(char *);
void freeTokens(Token *);
int isunderscore(char);
int isValidToken(char *);
void findLongestToken ( char *token, Token* tokArr, int* tokenCount );
Token **findLongestToken(char *, Token **);

#endif //_LEXER_H_
Loading