feat: history

- fix: move many things to heap

Makefile

@@ -7,9 +7,11 @@ CFLAGS ?= -Wall
 
 ifeq ($(RELEASE),true)
 	CFLAGS += -O3
+else
+	CFLAGS += --debug
 endif
 
-.PHONY: clean release-$(RELEASE)
+.PHONY: clean grind release-$(RELEASE)
 
 all: dist/msh
 
@@ -21,3 +23,6 @@ dist:
 
 clean:
 	rm -rf dist
+
+grind:
+	valgrind --leak-check=full --show-leak-kinds=all ./dist/msh

src/msh.c

@@ -17,6 +17,8 @@
 #define HISTORY_FILE_NAME "/history.log"
 #define LOCAL_SHARE_DIRNAME "/.local/share/msh"
 
+#define DEFAULTLINECAPACITY     128
+#define DEFAULTTOKENSCAPACITY   32
 
 const int LINESIZE = 512;
 
@@ -138,16 +140,19 @@ char* status_string(int status) {
 
 int main(int argc, char** argv) {
     int retval = 0;
-    char*   tokens[LINESIZE] = {};
+    char*   line = NULL;
-    char**  args;
+    size_t  linecapacity = 0;
-    char    line[LINESIZE] = {};
     char    prompt[LINESIZE] = {};
-    int     linelen = 0;
+    size_t  linelen = 0;
-    char*   tokenwork;
+    char*   tokenwork = NULL;
-    char*   token;
+    size_t  tokenworkcapacity = 0;
-    int     ntokens = 0;
+    char**  tokens = NULL;
+    size_t  tokenscapacity = 0;
+    size_t  ntokens = 0;
+    char**  history = NULL;
+    size_t  historycapacity = 0;
+    size_t  historyi = 0;
     
-    int i;
 
     int pid;
     int laststatus = 0;
@@ -246,6 +251,25 @@ int main(int argc, char** argv) {
     }
 
 
+    // Initialize memory
+    tokens = calloc(DEFAULTTOKENSCAPACITY, sizeof(char*));
+    if (tokens == NULL) {
+        retval = 1;
+        goto cleanup;
+    }
+    memset(tokens, 0, DEFAULTTOKENSCAPACITY * sizeof(char*));
+    tokenscapacity = DEFAULTTOKENSCAPACITY;
+
+    tokenwork = malloc(DEFAULTLINECAPACITY);
+    if (tokenwork == NULL) {
+        retval = 1;
+        goto cleanup;
+    }
+    tokenworkcapacity = DEFAULTLINECAPACITY;
+
+    historycapacity = 16;
+    history = calloc(historycapacity, sizeof(char*));
+
     // Main loop
     while(1) {
         char* result = getcwd(pwd, LINESIZE - 1);
@@ -289,7 +313,10 @@ int main(int argc, char** argv) {
 
         tcsetattr(fileno(stdin), 0, &term);
 
-        memset(line, 0, LINESIZE);
+        line = malloc(DEFAULTLINECAPACITY);
+        linecapacity = DEFAULTLINECAPACITY;
+
+        memset(line, 0, linecapacity);
 
         while ((readc = getchar()) != '\n') {
             if (readc == EOF) {
@@ -351,6 +378,19 @@ int main(int argc, char** argv) {
             cursor++;
             linelen++;
 
+            // Are we out of capacity? Double line length
+            if (linelen >= linecapacity - 1) {
+                linecapacity *= 2;
+                line = realloc(line, linecapacity);
+                if (line == NULL) {
+                    fprintf(stderr, "Error: Failed to re-allocated line buffer");
+                    retval = 1;
+                    goto cleanup;
+                }
+
+                memset(line + linecapacity / 2, 0, linecapacity / 2);
+            }
+
 print_prompt:
             // Manual echo
             printf(ANSI_ESC "[2K" ANSI_ESC "[0G" "%s%s", prompt, line);
@@ -369,19 +409,58 @@ print_prompt:
         fprintf(historyfile, "%s\n", line);
         fflush(historyfile);
         
+        if (tokenworkcapacity < linelen - 1) {
+            tokenworkcapacity *= 2;
+            tokenwork = realloc(tokenwork, tokenworkcapacity);
+        }
+
+        memset(tokenwork, 0, tokenworkcapacity);
+        tokenwork = strncpy(tokenwork, line, linelen);
+        if (tokenwork == NULL) {
+            retval = 1;
+            goto cleanup;
+        }
+
+
+        // TEMPORARY
+        if (historyi >= historycapacity) {
+            historycapacity *= 2;
+            history = reallocarray(history, historycapacity, sizeof(char*));
+
+            if (history == NULL) {
+                retval = 1;
+                goto cleanup;
+            }
+        }
+        // change ownership of line to history
+        history[historyi++] = line;
+        line = NULL;
+
+        char* tokensarg = tokenwork;
+        ntokens = 0;
+
         // Split into tokens
-        for (tokenwork = line, i = 0; ; tokenwork = NULL, i++) {
+        for (;; ntokens++) {
-            token = strtok(tokenwork, " \t");
+            char* token = strtok(tokensarg, " \t");
             if (token == NULL) {
                 break;
             }
 
-            tokens[i] = token;
+            tokens[ntokens] = token;
+
+            if (ntokens >= tokenscapacity - 1) {
+                tokenscapacity *= 2;
+                tokens = reallocarray(tokens, tokenscapacity, sizeof(char*));
+            }
+
+            // required to be NULL for second strtok invocation
+            if (tokensarg != NULL) {
+                tokensarg = NULL;
+            }
         }
 
-        ntokens = i;
         tokens[ntokens] = NULL;
-        args = &tokens[1];
+        char** args = &tokens[1];
 
         if (ntokens == 0) {
             continue;
@@ -399,17 +478,32 @@ print_prompt:
             continue;
         }
 
+        if (strcmp("history", tokens[0]) == 0) {
+            for (int i = 0; i < historycapacity; i++) {
+                if (history[i] == NULL) {
+                    break;
+                }
+
+                printf("%.3d: %s\n", i, history[i]);
+            }
+
+            laststatus = 0;
+            continue;
+        }
+
         // Execute command
         pid = fork();
 
         if(pid == 0) {
-            return execvpe(tokens[0], tokens, environ);
+            retval = execvpe(tokens[0], tokens, environ);
+            goto cleanup;
         } else {
             waitpid(pid, &wstatus, 0);
 
             laststatus = WEXITSTATUS(wstatus);
         }
 
+
     }
 
 
@@ -425,6 +519,30 @@ cleanup:
         fflush(historyfile);
         fclose(historyfile);
     }
+
+    if (line != NULL) {
+        free(line);
+    }
+
+    if (tokenwork != NULL) {
+        free(tokenwork);
+    }
+
+    if (tokens != NULL) {
+        free(tokens);
+    }
+
+    if (history != NULL) {
+        for (int i = 0; i < historycapacity; i++) {
+            if (history[i] != NULL) {
+                free(history[i]);
+            }
+        }
+
+        free(history);
+    }
+
+
     tcsetattr(fileno(stdin), 0, &orig_term);
     return retval;
 }