SysCall

1.  #Makefile
2. CC = gcc
3. FLAGS = -g -Wall -lcurses
4. SOURCE = main.c size.c
5. OBJC = main.o size.o
6. PROJ = less
7. INCLUDE = -I include
8.  
9. vpath %.c src/
10. vpath %.h include/
11.  
12. $(PROJ):$(OBJC)
13.     $(CC) $(FLAGS) $^ -o $@
14.  
15. main.o:$(SOURCE)
16.     $(CC) $(INCLUDE) $^ -c $(FLAGS)

 #Makefile
CC = gcc
FLAGS = -g -Wall -lcurses
SOURCE = main.c size.c
OBJC = main.o size.o
PROJ = less
INCLUDE = -I include

vpath %.c src/
vpath %.h include/

$(PROJ):$(OBJC)
	$(CC) $(FLAGS) $^ -o $@

main.o:$(SOURCE)
	$(CC) $(INCLUDE) $^ -c $(FLAGS)

1.  /* main.c */
2. #include <stdio.h>
3. #include <stdlib.h>
4. #include <curses.h>
5. #include <message.h>
6.  
7. #define UP       1
8. #define DOWN     2
9. #define RIGHT    3
10. #define LEFT     4
11. #define LINE_TAB 6
12. #define LINE_TOP 7
13. #define LINE_END 8
14. #define QUIT     9
15.  
16. extern long line_count(FILE *fp);
17. extern int getkey(void);
18. void close_fd(void);
19.  
20. FILE *fp = NULL;
21.  
22. int main(int argc, char **argv)
23. {
24.     int term_w   = 0;
25.     int pad_line = 0;
26.     int pad_w    = 0;
27.     int pad_y;
28.     int pad_x;
29.     char *buff;
30.     int ch;
31.     int answer = 1;
32.  
33.     WINDOW *pad;
34.  
35.     if(argc < 2) {
36.         print_help();
37.         print_version();
38.         exit(EXIT_FAILURE);
39.     }
40.  
41.     if((fp = fopen(argv[1], "r")) == NULL) {
42.         perror("fopen(3)");
43.         exit(EXIT_FAILURE);
44.     }
45.  
46.     atexit(close_fd);
47.  
48.     while(feof(fp) == 0) {
49.         term_w = line_count(fp);
50.         pad_line++;
51.         if(term_w > pad_w)
52.             pad_w = term_w;
53.     }
54.  
55.     if(initscr() == NULL) {
56.         perror("initscr(3)");
57.         exit(EXIT_FAILURE);
58.     }
59.  
60.     cbreak();
61.     noecho();
62.  
63.     scrollok(stdscr, FALSE);
64.  
65.     pad = newpad(pad_line, ++pad_w);
66.  
67.     fseek(fp, 0, SEEK_SET);
68.     buff = (char *)malloc(sizeof(char) * pad_w);
69.  
70.     for(pad_y = 0; pad_y < pad_line; pad_y++) {
71.         fgets(buff, pad_w, fp);
72.         mvwprintw(pad, pad_y, 0, "%s", buff);
73.     }
74.     free(buff);
75.     refresh();
76.     prefresh(pad, 0, 0, 0, 0, LINES - 1, COLS -1);
77.     pad_y = 0;
78.     pad_x = 0;
79.  
80.     curs_set(0);
81.  
82.     while(answer == 1) {
83.         ch = getkey();
84.  
85.         switch(ch) {
86.             case DOWN:
87.                 if(pad_y < pad_line - LINES)
88.                     ++pad_y;
89.                 break;
90.             case UP:
91.                 if(pad_y == 0) 
92.                     pad_y += 0;
93.                 else if(pad_y != 0)
94.                     --pad_y;
95.                 break;
96.             case LINE_TAB:
97.                 if(pad_y < pad_line - LINES - 20)
98.                     pad_y += 20;
99.                 break;
100.             case QUIT:
101.                 answer = 0;
102.                 break;
103.             case LINE_TOP:
104.                 pad_y = 0;
105.                 break;
106.             case LINE_END:
107.                 pad_y = pad_line - LINES;
108.                 break;
109.         }
110.         prefresh(pad, pad_y, pad_x, 0, 0, LINES - 1, COLS - 1);
111.     }
112.  
113.     exit(EXIT_SUCCESS);
114. }
115.  
116. void close_fd(void) {
117.     endwin();
118.     fclose(fp);
119. }

 /* main.c */
#include <stdio.h>
#include <stdlib.h>
#include <curses.h>
#include <message.h>

#define UP       1
#define DOWN     2
#define RIGHT    3
#define LEFT     4
#define LINE_TAB 6
#define LINE_TOP 7
#define LINE_END 8
#define QUIT     9

extern long line_count(FILE *fp);
extern int getkey(void);
void close_fd(void);

FILE *fp = NULL;

int main(int argc, char **argv)
{
    int term_w   = 0;
    int pad_line = 0;
    int pad_w    = 0;
    int pad_y;
    int pad_x;
    char *buff;
    int ch;
    int answer = 1;

    WINDOW *pad;

    if(argc < 2) {
        print_help();
        print_version();
        exit(EXIT_FAILURE);
    }

    if((fp = fopen(argv[1], "r")) == NULL) {
        perror("fopen(3)");
        exit(EXIT_FAILURE);
    }

    atexit(close_fd);

    while(feof(fp) == 0) {
        term_w = line_count(fp);
        pad_line++;
        if(term_w > pad_w)
            pad_w = term_w;
    }

    if(initscr() == NULL) {
        perror("initscr(3)");
        exit(EXIT_FAILURE);
    }

    cbreak();
    noecho();

    scrollok(stdscr, FALSE);

    pad = newpad(pad_line, ++pad_w);

    fseek(fp, 0, SEEK_SET);
    buff = (char *)malloc(sizeof(char) * pad_w);

    for(pad_y = 0; pad_y < pad_line; pad_y++) {
        fgets(buff, pad_w, fp);
        mvwprintw(pad, pad_y, 0, "%s", buff);
    }
    free(buff);
    refresh();
    prefresh(pad, 0, 0, 0, 0, LINES - 1, COLS -1);
    pad_y = 0;
    pad_x = 0;

    curs_set(0);

    while(answer == 1) {
        ch = getkey();

        switch(ch) {
            case DOWN:
                if(pad_y < pad_line - LINES)
                    ++pad_y;
                break;
            case UP:
                if(pad_y == 0) 
                    pad_y += 0;
                else if(pad_y != 0)
                    --pad_y;
                break;
            case LINE_TAB:
                if(pad_y < pad_line - LINES - 20)
                    pad_y += 20;
                break;
            case QUIT:
                answer = 0;
                break;
            case LINE_TOP:
                pad_y = 0;
                break;
            case LINE_END:
                pad_y = pad_line - LINES;
                break;
        }
        prefresh(pad, pad_y, pad_x, 0, 0, LINES - 1, COLS - 1);
    }

    exit(EXIT_SUCCESS);
}

void close_fd(void) {
    endwin();
    fclose(fp);
}

1.  /* size.c */
2. #include <stdio.h>
3. #include <stdlib.h>
4. #include <termios.h>
5. #include <unistd.h>
6. #include <sys/ioctl.h>
7.  
8. #define UP       1
9. #define DOWN     2
10. #define RIGHT    3
11. #define LEFT     4
12. #define LINE_TAB 6
13. #define LINE_TOP 7
14. #define LINE_END 8
15. #define QUIT     9
16.  
17. long line_count(FILE *fp) {
18.     long read_line = 0;
19.     int ch;
20.  
21.     while((ch = fgetc(fp)) != '\n' && ch != EOF) 
22.         read_line++;
23.  
24.  
25.     return read_line;
26. }
27.  
28. int getkey(void) {
29.     char ch;
30.     struct termios tty, save;
31.  
32.     if(ioctl(0, TCGETS, &tty) == EOF) {
33.         perror("ioctl(2)");
34.         exit(EXIT_FAILURE);
35.     }
36.     save = tty;
37.     tty.c_cc[VMIN] = 1;
38.     tty.c_lflag &= ~ECHO;
39.  
40.     if(ioctl(0, TCSETS, &tty) == EOF) {
41.         perror("ioctl(2)");
42.         exit(EXIT_FAILURE);
43.     }
44.  
45.     if(read(0, &ch, 1) == EOF) {
46.         perror("read(2)");
47.         exit(EXIT_FAILURE);
48.     }
49.  
50.     if(ch == 'k')
51.         return UP;
52.     else if(ch == 'j')
53.         return DOWN;
54.     else if(ch == 'q') {
55.         ioctl(0, TCSETS, &save);
56.         return QUIT;
57.     }
58.     else if(ch == 'd')
59.         return LINE_TAB;
60.     else if(ch == 'G')
61.         return LINE_END;
62.     else if(ch == 'g') {
63.         if(read(0, &ch, 1) == EOF) {
64.             perror("read(2)");
65.             exit(EXIT_FAILURE);
66.         }
67.         if(ch == 'g')
68.             return LINE_TOP;
69.         else
70.             return 0;
71.     }
72.  
73.     return EOF;
74. }

 /* size.c */
#include <stdio.h>
#include <stdlib.h>
#include <termios.h>
#include <unistd.h>
#include <sys/ioctl.h>

#define UP       1
#define DOWN     2
#define RIGHT    3
#define LEFT     4
#define LINE_TAB 6
#define LINE_TOP 7
#define LINE_END 8
#define QUIT     9

long line_count(FILE *fp) {
    long read_line = 0;
    int ch;

    while((ch = fgetc(fp)) != '\n' && ch != EOF) 
        read_line++;


    return read_line;
}

int getkey(void) {
    char ch;
    struct termios tty, save;

    if(ioctl(0, TCGETS, &tty) == EOF) {
        perror("ioctl(2)");
        exit(EXIT_FAILURE);
    }
    save = tty;
    tty.c_cc[VMIN] = 1;
    tty.c_lflag &= ~ECHO;

    if(ioctl(0, TCSETS, &tty) == EOF) {
        perror("ioctl(2)");
        exit(EXIT_FAILURE);
    }

    if(read(0, &ch, 1) == EOF) {
        perror("read(2)");
        exit(EXIT_FAILURE);
    }

    if(ch == 'k')
        return UP;
    else if(ch == 'j')
        return DOWN;
    else if(ch == 'q') {
        ioctl(0, TCSETS, &save);
        return QUIT;
    }
    else if(ch == 'd')
        return LINE_TAB;
    else if(ch == 'G')
        return LINE_END;
    else if(ch == 'g') {
        if(read(0, &ch, 1) == EOF) {
            perror("read(2)");
            exit(EXIT_FAILURE);
        }
        if(ch == 'g')
            return LINE_TOP;
        else
            return 0;
    }

    return EOF;
}

1.  /* message.h */
2. void print_help(void) {
3.     printf("Usage: ./less [Filename]\n");
4. }
5.  
6. void print_version(void) {
7.     printf("Version: 1.0.0\n");
8. }

 /* message.h */
void print_help(void) {
    printf("Usage: ./less [Filename]\n");
}

void print_version(void) {
    printf("Version: 1.0.0\n");
}