get started on homework11

hw11/tiny/Makefile

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+CC = gcc
+CFLAGS = -O2 -Wall -I .
+
+# This flag includes the Pthreads library on a Linux box.
+# Others systems will probably require something different.
+LIB = -lpthread
+
+all: tiny cgi
+
+tiny: tiny.c csapp.o
+	$(CC) $(CFLAGS) -o tiny tiny.c csapp.o $(LIB)
+
+csapp.o: csapp.c
+	$(CC) $(CFLAGS) -c csapp.c
+
+cgi:
+	(cd cgi-bin; make)
+
+clean:
+	rm -f *.o tiny *~
+	(cd cgi-bin; make clean)
+

hw11/tiny/cgi-bin/Makefile

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+CC = gcc
+CFLAGS = -O2 -Wall -I ..
+
+all: adder
+
+adder: adder.c
+	$(CC) $(CFLAGS) -o adder adder.c
+
+clean:
+	rm -f adder *~

hw11/tiny/cgi-bin/adder.c

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+/*
+ * adder.c - a minimal CGI program that adds two numbers together
+ */
+/* $begin adder */
+#include "csapp.h"
+
+int main(void) {
+    char *buf, *p;
+    char arg1[MAXLINE], arg2[MAXLINE], content[MAXLINE];
+    int n1=0, n2=0;
+
+    /* Extract the two arguments */
+    if ((buf = getenv("QUERY_STRING")) != NULL) {
+	p = strchr(buf, '&');
+	*p = '\0';
+	strcpy(arg1, buf);
+	strcpy(arg2, p+1);
+	n1 = atoi(arg1);
+	n2 = atoi(arg2);
+    }
+
+    /* Make the response body */
+    sprintf(content, "Welcome to add.com: ");
+    sprintf(content, "%sTHE Internet addition portal.\r\n<p>", content);
+    sprintf(content, "%sThe answer is: %d + %d = %d\r\n<p>", 
+	    content, n1, n2, n1 + n2);
+    sprintf(content, "%sThanks for visiting!\r\n", content);
+
+    /* Generate the HTTP response */
+    printf("Connection: close\r\n");
+    printf("Content-length: %d\r\n", (int)strlen(content));
+    printf("Content-type: text/html\r\n\r\n");
+    printf("%s", content);
+    fflush(stdout);
+
+    exit(0);
+}
+/* $end adder */