From: Armaan Bhojwani <me@armaanb.net>
Date: Sun, 9 May 2021 03:11:26 +0000 (-0400)
Subject: Clean up and implement calloc/realloc
X-Git-Url: https://git.armaanb.net/?p=mmenu.git;a=commitdiff_plain;h=c4a0b3ce0963cf106043b86dada809efc990cc2d

Clean up and implement calloc/realloc

* Replace /* comments with //
* Replace malloc with calloc + realloc
* Remove extra space between function and arguments
* Check for failed *allocs
---

diff --git a/mmenu.c b/mmenu.c
index 2dd8c75..b00af5a 100644
--- a/mmenu.c
+++ b/mmenu.c
@@ -10,6 +10,14 @@ struct MemoryStruct {
 	size_t size;
 };
 
+int
+memfail(void)
+{
+	printf("ERROR: Out of memory\n");
+	exit(4);
+}
+
+
 static size_t
 memback(void *contents, size_t size, size_t nmemb, void *userp)
 {
@@ -17,11 +25,7 @@ memback(void *contents, size_t size, size_t nmemb, void *userp)
 	struct MemoryStruct *mem = (struct MemoryStruct *)userp;
 
 	char *ptr = realloc(mem->memory, mem->size + realsize + 1);
-	if(!ptr) {
-		/* out of memory! */
-		printf("not enough memory (realloc returned NULL)\n");
-		return 0;
-	}
+	if (!ptr) memfail();
 
 	mem->memory = ptr;
 	memcpy(&(mem->memory[mem->size]), contents, realsize);
@@ -44,8 +48,8 @@ main(int argc, char *argv[])
 	}
 
 	struct MemoryStruct chunk;
-	chunk.memory = malloc(1);  // will be grown as needed by the realloc above
-	chunk.size = 0; // no data at this point
+	chunk.memory = malloc(1); // Grown as needed by the realloc in memback()
+	chunk.size = 0; // No data yet
 
 	curl_easy_setopt(curl, CURLOPT_URL,
 			"https://nobilis.nobles.edu/skyworld/castlemenu.php");
@@ -67,32 +71,41 @@ main(int argc, char *argv[])
 	// Parse HTML
 	printf("INFO: Parsing HTML\n");
 	bool intag = false;
-	char *outp = (char *) malloc(strlen(chunk.memory) + 1); // TODO: Realloc?
-	strcpy(outp, "");
+	char *outp = (char *) calloc(1, sizeof(char));
+	if (!outp) memfail();
 
 	// Extract text from between HTML tags
+	int j = 1;
 	for (int i = 345; i < strlen(chunk.memory); i++) {
 		char c = chunk.memory[i];
 		if (c == '<') intag = true;
-		if (!intag) strncat(outp, &c, 1);
+		if (!intag) {
+			j++;
+			outp = (char *) realloc(outp, j);
+			if (!outp) memfail();
+			strncat(outp, &c, 1);
+		}
 		if (c == '>') intag = false;
 	}
 
 	// Strip empty newlines
-	char *nl = (char *) malloc(strlen(outp));
-	strncpy(nl, "\0", 1);
+	char *nl = (char *) calloc(1, sizeof(char));
+	if (!nl) memfail();
+
 	for (int i = 0; i < strlen(outp) - 1; i++) {
 		if (outp[i] == '\n' && outp[i+1] == '\n') i+=4;
+		nl = (char *) realloc(nl, i);
+		if (!nl) memfail();
 		strncat(nl, &outp[i], 1);
 	}
 
 	// Initialize motif
-	Widget             toplevel;
-	XtAppContext       app;
-	Widget             text_w;
-	Arg                args[4];
+	Widget       toplevel;
+	XtAppContext app;
+	Widget       text_w;
+	Arg          args[4];
 
-	XtSetLanguageProc (NULL, NULL, NULL);
+	XtSetLanguageProc(NULL, NULL, NULL);
 	toplevel = XtVaOpenApplication (&app, "Castle Menu", NULL, 0, &argc, argv,
 			NULL, sessionShellWidgetClass, NULL);