--- joko/Uni/BSArch/01/prime.c	2006/05/13 12:06:38	1.10
+++ joko/Uni/BSArch/01/prime.c	2006/05/15 11:25:40	1.15
@@ -1,10 +1,15 @@
-/* $Id: prime.c,v 1.10 2006/05/13 12:06:38 joko Exp $ */
+/* $Id: prime.c,v 1.15 2006/05/15 11:25:40 franky Exp $ */
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <math.h>
 #include <limits.h>
 #include <errno.h>
 
+#ifdef _MSC_VER
+#define snprintf _snprintf
+#endif
+
 #define BOOL int
 #define TRUE 1
 #define FALSE 0
@@ -13,16 +18,19 @@
 #define PRINTERROR(message) fprintf(stderr, "ERROR: %s\n", message)
 #define PRINTWARNING(message) fprintf(stderr, "WARNING: %s\n", message)
 
+#define MAX_LINE_LENGTH 80
+
+
 /* check for prime number */
 BOOL is_prime(long int number)
 {
-	int i;
-	
+	int i,sq;
 	/* negative values, 0 and 1 are never prime numbers */
 	if (number < 2) return FALSE;
+	sq=sqrt(number);
 	
 	/* check all numbers 2..sqrt(number) for being a prime number */
-	for (i=2; i*i <= number; i++) {
+	for (i=2; i <= sq; i++) {
 		if ((number % i) == 0)
 			return FALSE;
 	}
@@ -30,28 +38,37 @@
 }
 
 /* convert from string to long int, with error checking */
-long int convert_number(const char *nptr) {
+long int convert_number(const char *nptr, BOOL warn) {
 	
 	char * endptr;
-	long int number = strtol(nptr, &endptr, 10);
-
 	errno = 0;
+	long int number;
+
+	number = strtol(nptr, &endptr, 10);
 	
 	/* invalid characters? */
 	if (*endptr != '\0') {
-		char message[254];
-		snprintf(message, 256, "Could not convert '%s' to a valid number.", nptr);
-		PRINTERROR(message);
-		exit(EXIT_FAILURE);
+		char message[256];
+		snprintf(message, 255, "Could not convert '%s' to a valid (integer) number.", nptr);
+		if(warn) 
+			PRINTWARNING(message);
+		else{
+			PRINTERROR(message);
+		 	exit(EXIT_FAILURE);
+		}
 	}
 	
 	/* invalid range? */
 	/* if (number == LONG_MAX || number == LONG_MIN) { */
 	if (errno == ERANGE) {
-		char message[254];
-		snprintf(message, 256, "Number is not in range of 'long int': %s", nptr);
-		PRINTERROR(message);
-		exit(EXIT_FAILURE);
+		char message[256];
+		snprintf(message, 255, "Number is not in range of 'long int': %s", nptr);
+		if(warn)
+			PRINTWARNING(message);
+		else{			
+			PRINTERROR(message);
+			exit(EXIT_FAILURE);
+		}
 	}
 	
 	return number;
@@ -69,57 +86,70 @@
 	/* (3) range mode */
 	if (argc > 2) {
 		long int i, j;
-		i = convert_number(argv[1]);
-		j = convert_number(argv[2]);
+		i = convert_number(argv[1],FALSE);
+		j = convert_number(argv[2],FALSE);
 		for (i; i< j; i++) {
 			PRINTPRIME(i);
 		}
 	
 	/* other modes */
 	} else {
-
+		int err;
 		/* try to open file for reading */
 		FILE * fp = fopen(argv[1], "r");
-		
+		err=errno;
 		/* (1) test-single-number mode: first argument is not a filename */
 		if (fp == NULL) {
-			long int number = convert_number(argv[1]);
+			long int number = convert_number(argv[1],TRUE);
+			if(err){
+				fprintf(stderr, "%s: %s\n", argv[1], strerror(err));
+				return -1;
+			}
 			PRINTPRIME(number);
 		
 		/* (2) file mode: read numbers from file */
 		} else {
-			char entry[81];
+			char line[MAX_LINE_LENGTH + 1];
 			long int number;
-			long int lineno = 0;
-			while (fgets(entry, 81, fp)) {
+			int line_length;
+			long int line_no = 0;
+			while (fgets(line, MAX_LINE_LENGTH + 1, fp)) {
 				
 				/* count line number (for warnings) */
-				lineno++;
+				line_no++;
 
+				line_length = strlen(line);
+				
 				/* skip empty lines */
-				if (strlen(entry) < 2) continue;
+				if (strlen(line) < 2) continue;
 
 				/* line handling: policy = skip exceeding lines */
 				
-				/* if last char is newline, strip it */
-				if (entry[strlen(entry)-1] == '\n') {
-					entry[strlen(entry)-1] = '\0';
-					
 				/* line exceeds max length */
-				} else {
+				if (line_length == MAX_LINE_LENGTH && line[line_length-1] != '\n') {
 					char message[254];
-					snprintf(message, 256, "Line too long (max 80 chars) in line number: %i", lineno);
+					snprintf(message, 256, "Line too long (max %i chars) in line number: %i", MAX_LINE_LENGTH, line_no);
 					PRINTWARNING(message);
 					
-					/* eat all characters until newline */
-					while (fgetc(fp) != 10);
+					/* eat all characters until newline or EOF */
+					while (1) {
+						int charcode = fgetc(fp);
+						if (charcode == 10 || charcode == EOF) break;
+					}
 					
 					/* skip this line from prime calculation */
 					continue;
 				}
 				
-				number = convert_number(entry);
+				/* if last char is newline, strip it */
+				if (line[line_length-1] == '\n') {
+					line[line_length-1] = '\0';
+				}
+				
+				/* finally: prime number calculation and output */
+				number = convert_number(line,FALSE);
 				PRINTPRIME(number);
+				
 			}
 			fclose(fp);
 		}