Reading file line by line - why I get the first line only? - c

Question

I have a task in university to write a C program which reads a file and counts the number of single and multi comments. The problem I have is that the second while() only reads the first line and so the returned comments are 0.
Previously I read the file character by character, but that's not the task requirement. Why does this program read only the first line and not the others?
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main(int argc, char **argv) {
FILE *fp;
int c, i = 0;
char path[256], ch, line[80];
unsigned int multi = 0;
unsigned int single = 0;
enum states {
PLAIN_TEXT,
SLASH,
STAR,
SINGLE_COMMENT,
MULTI_COMMENT,
QUOTES
} state = PLAIN_TEXT;
printf("Write file's name\n");
gets(path)
fp = fopen(path, "r");
if (!fp) {
// give an error message
} else {
while (fgets(line, sizeof(line), fp) != NULL) {
while (i < sizeof(line)) {
printf("%d.%c", i, line[i]);
switch (state) {
case PLAIN_TEXT:
switch (line[i]) {
case '/': i++;
state = SLASH;
break; // found a slash. In the next loop the switch argument will be SLASH
case '"': i++;
state = QUOTES;
break; // found a quote. Quoted text (there might be a '//' inside)
default: i++;
break; // found an ordinary character
}
break;
case QUOTES:
switch (line[i]) {
case '"': i++;
state = PLAIN_TEXT;
break; // Gets out the string;
case ' ':i++;
state = PLAIN_TEXT;
break;
default: i++;
state = QUOTES;
break; // Still a quoted text;
}
break;
case SLASH:
switch (line[i]) {
case '/': i++;
state = SINGLE_COMMENT;
break; // found a slash => a possible single comment found
case '*': i++;
state = MULTI_COMMENT;
break; // found a star => a possible multi comment found
default: i++;
state = PLAIN_TEXT;
break; // found an ordinary character
}
break;
case STAR:
switch (line[i]) {
case '/': i++;
state = PLAIN_TEXT;
multi++;
break; // Increments the multi comment and the next characher will be treated as a plain_taxt
default: i++;
state = MULTI_COMMENT;
break; // Still multi comment
}
break;
case SINGLE_COMMENT:
switch (line[i]) {
case '\n':i++;
state = PLAIN_TEXT;
single++;
break; // End of the single comment line. Increment the counter and the next character will be treated as a plain_text
default: i++;
break;
}
break;
case MULTI_COMMENT:
switch (line[i]) {
case '*': i++;
state = STAR;
break; // Found a multi comment. The next state will be star.
default: i++;
break;
}
break;
default: i++;
break;
}
}
}
fclose(fp);
printf("Single-comment : %8u\n", single);
printf("Multi-comment : %8u\n", multi);
}
return 0;
}

Answer 1

To enumerate the characters on the line, you must reinitialize i to 0 for each line and stop at the null terminator or at the newline character