11 |
|
|
12 |
#define PRINTPRIME(x) if (is_prime(x)) printf("%i\n", x) |
#define PRINTPRIME(x) if (is_prime(x)) printf("%i\n", x) |
13 |
#define PRINTERROR(message) fprintf(stderr, "ERROR: %s\n", message) |
#define PRINTERROR(message) fprintf(stderr, "ERROR: %s\n", message) |
14 |
|
#define PRINTWARNING(message) fprintf(stderr, "WARNING: %s\n", message) |
15 |
|
|
16 |
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#define MAX_LINE_LENGTH 80 |
17 |
|
|
18 |
|
|
19 |
/* check for prime number */ |
/* check for prime number */ |
20 |
BOOL is_prime(long int number) |
BOOL is_prime(long int number) |
35 |
/* convert from string to long int, with error checking */ |
/* convert from string to long int, with error checking */ |
36 |
long int convert_number(const char *nptr) { |
long int convert_number(const char *nptr) { |
37 |
|
|
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errno = 0; |
|
38 |
char * endptr; |
char * endptr; |
39 |
long int number = strtol(nptr, &endptr, 10); |
long int number = strtol(nptr, &endptr, 10); |
40 |
|
|
41 |
|
errno = 0; |
42 |
|
|
43 |
/* invalid characters? */ |
/* invalid characters? */ |
44 |
if (*endptr != '\0') { |
if (*endptr != '\0') { |
91 |
|
|
92 |
/* (2) file mode: read numbers from file */ |
/* (2) file mode: read numbers from file */ |
93 |
} else { |
} else { |
94 |
char entry[11]; |
char line[MAX_LINE_LENGTH + 1]; |
95 |
while (fgets(entry, 11, fp)) { |
long int number; |
96 |
long int number = convert_number(entry); |
int line_length; |
97 |
|
long int line_no = 0; |
98 |
|
while (fgets(line, MAX_LINE_LENGTH + 1, fp)) { |
99 |
|
|
100 |
|
/* count line number (for warnings) */ |
101 |
|
line_no++; |
102 |
|
|
103 |
|
line_length = strlen(line); |
104 |
|
|
105 |
|
/* skip empty lines */ |
106 |
|
if (strlen(line) < 2) continue; |
107 |
|
|
108 |
|
/* line handling: policy = skip exceeding lines */ |
109 |
|
|
110 |
|
/* line exceeds max length */ |
111 |
|
if (line_length == MAX_LINE_LENGTH && line[line_length-1] != '\n') { |
112 |
|
char message[254]; |
113 |
|
snprintf(message, 256, "Line too long (max %i chars) in line number: %i", MAX_LINE_LENGTH, line_no); |
114 |
|
PRINTWARNING(message); |
115 |
|
|
116 |
|
/* eat all characters until newline or EOF */ |
117 |
|
while (1) { |
118 |
|
int charcode = fgetc(fp); |
119 |
|
if (charcode == 10 || charcode == EOF) break; |
120 |
|
} |
121 |
|
|
122 |
|
/* skip this line from prime calculation */ |
123 |
|
continue; |
124 |
|
} |
125 |
|
|
126 |
|
/* if last char is newline, strip it */ |
127 |
|
if (line[line_length-1] == '\n') { |
128 |
|
line[line_length-1] = '\0'; |
129 |
|
} |
130 |
|
|
131 |
|
/* finally: prime number calculation and output */ |
132 |
|
number = convert_number(line); |
133 |
PRINTPRIME(number); |
PRINTPRIME(number); |
134 |
|
|
135 |
} |
} |
136 |
fclose(fp); |
fclose(fp); |
137 |
} |
} |