File content as of revision 19:bf5f5ea4e762:

#include "SimpleShell.h"
#include <ctype.h>
#include <string>

#define ESC     0x1b
#define UP      0x41
#define DOWN    0x42
#define RIGHT   0x43
#define LEFT    0x44
#define HOME    0x31
#define INS     0x32
#define DEL     0x33
#define PGUP    0x35
#define PGDN    0x36
#define TAIL    0x7e


char *SimpleShell::canon(char *path) {
    static char result[MAXBUF];
    
    if (path[0] != '/') {
        strncpy(result, _cwd, MAXBUF);
        strcat(result, "/");
    }
    strcat(result, path);
    
    return result;
}


SimpleShell::SimpleShell()
{
    lookupEnd = 0;

    // Built-in shell commands
    attach(callback(this, &SimpleShell::help), "help");
    attach(callback(this, &SimpleShell::pwd), "pwd");
    attach(callback(this, &SimpleShell::cat), "cat");
    attach(callback(this, &SimpleShell::cd), "cd");
    attach(callback(this, &SimpleShell::rm), "rm");
    attach(callback(this, &SimpleShell::touch), "touch");
    attach(callback(this, &SimpleShell::ls), "ls");
}


void SimpleShell::help(int argc, char **argv)
{
    printf("Available commands: ");
    for (int i=0; i < lookupEnd; i++) {
        printf("%s ", lookup[i].command);
    }
    printf("\n\n");
}


void SimpleShell::cd(int argc, char **argv) 
{
    if (argc == 2) {
        strncpy(_cwd, argv[1], MAXBUF);
    } else {
        puts("usage: cd directory");
    }
    return;
}


void SimpleShell::pwd(int argc, char **argv)
{
    puts(_cwd);
    return;
}


void SimpleShell::ls(int argc, char **argv)
{
    DIR *d;
    struct dirent *p;
    char *path;

    if (argc == 1) {
        path = _cwd;
    } else if (argc == 2) {
        path = argv[1];
    } else {
        puts("usage: ls [directory]");
        return;
    }
    
    int cols=0;
    if ((d = opendir(path)) != NULL) {
        while ((p = readdir(d)) != NULL) {
            if (p->d_name && p->d_name[0] != 0xff) {
                if (cols++ > 3) {
                    putc('\n', stdout);
                    cols = 0;
                }
                printf("%-15s  ", p->d_name);
            }
        }
        putc('\n', stdout);
        if (cols < 3)
            putc('\n', stdout);
        closedir(d);
    } else {
        puts(path);
        puts(": No such directory\n");
    }

    return;
}


void SimpleShell::rm(int argc, char **argv)
{
    if (argc >= 2) {
        for (int i=1; i < argc; i++) {
            if (remove(canon(argv[i]))) {
                printf("%s: cannot remove\n", argv[i]);
            }
        }
    } else {
        puts("usage: rm [file1 [file2 ...]]");
    }
}


void SimpleShell::touch(int argc, char **argv)
{
    FILE *fp;

    if (argc >= 2) {
        for (int i=1; i < argc; i++) {
            if ((fp = fopen(canon(argv[i]), "w")) != NULL) {
                fclose(fp);
            } else {
                printf("%s: cannot touch\n", argv[1]);
            }
        }
    } else {
        puts("usage: touch [file1 [file2 ...]]");
    }
}


void SimpleShell::cat(int argc, char **argv)
{
    FILE *fp;
    //int status=0;
    char *buf = new char[MAXBUF];
    
    for (int i=1; i < argc; i++) {
        //resolveDirectory(path, arg);
        if ((fp = fopen(canon(argv[i]), "r")) != NULL) {
            while (!feof(fp)) {
                fgets(buf, MAXBUF-1, fp);
                fputs(buf, stdout);
            }
            fclose(fp);
        } else {
            fputs(argv[i], stdout);
            fputs(": No such file\n", stdout);
            //status = 1;
        }
    }
    delete[] buf;

    return;
}


void SimpleShell::run()
{
    bool done=false;
    callback_t cb;
    //int status; // TODO implement command status return
    std::string x;
    
    // Set current working directory
    strncpy(_cwd, "/etc", MAXBUF);

    printf("Type help for assistance.\n");
    help(0, NULL);   
    while (!done) {
        printPrompt();
        readCommand();
        if (argv[0]) { // skip blank command
            if (cb = findCommand()) {
                cb.call(argc, argv);
            } else {
                printf("command <%s> not found\n", argv[0]);
            }
        }
    }
    puts("exiting shell\n");

    return;
}


void SimpleShell::attach(callback_t cb, char *command) 
{  
    if (lookupEnd < MAXLOOKUP) {
        lookup[lookupEnd].cb = cb;
        lookup[lookupEnd].command = command;
        lookupEnd++;
    }
        
    return;
}


SimpleShell::callback_t SimpleShell::findCommand()
{
    SimpleShell::callback_t cb=NULL;
    
    for (int i=0; i < lookupEnd; i++) {
        if (strncmp(argv[0], lookup[i].command, MAXBUF) == 0) {
            cb = lookup[i].cb;
            break;
        }
    }
    
    return cb;
}


void SimpleShell::printPrompt()
{
    fputc('(', stdout);
    fputs(_cwd, stdout);
    fputs(")# ", stdout);
    
    return;
}


void SimpleShell::readCommand()
{
    int i=0;
    char c;
    bool done = false;
    static char cmd[MAXBUF];
    
    memset(cmd, 0, MAXBUF);
    do {
        cmd[i] = 0;
        c = fgetc(stdin);
        if (c == '\r') { // if return is hit, we're done, don't add \r to cmd
            done = true;
        } else if (c == ESC) { // keyboard escape codes (arrow keys, etc)
            int c2 = getchar();
            int c3 = getchar();

            if (c2 == 0x4f && c3 == 0x46) {
                printf("<END>");
            } else if (c2 == 0x5b) {

                if (c3 == UP) {
                    printf("<UP>");
                } else if (c3 == DOWN) {
                    printf("<DOWN>");
                } else if (c3 == RIGHT) {
                    printf("<RIGHT>");
                } else if (c3 == LEFT) {
                    printf("<LEFT>");
                } else if (c3 == HOME || c3 == INS || c3 == DEL ||
                           c3 == PGUP || c3 == PGDN) {
                    char c4 = getchar();
                    if (c4 == TAIL) {
                        if (c4 == HOME) {
                            printf("<HOME>");
                        } else if (c4 == INS) {
                            printf("<INS>");
                        } else if (c4 == DEL) {
                            printf("<DEL>");
                        } else if (c4 == PGUP) {
                            printf("<PGUP>");
                        } else if (c4 == PGDN) {
                            printf("<PGDN>");
                        }//if
                    }//if
                }//if
            }//if            
            //printf("\n");
        } else if (i < MAXBUF-1) {
            if (c == 0x7f || c == '\b') { // backspace or delete
                if (i > 0) { // if we're at the beginning, do nothing
                    i--;
                    fputs("\b \b", stdout);
                }
            } else {
                if (isprint(c))
                    fputc(c, stdout);
                cmd[i++] = c;
            }
        }

    } while (!done);
    fputc('\n', stdout);

    // remove leading/trailing whitespace
    char *s = cmd;
    while (isspace(*s)) {
        s++;
    }
    for (int j=i; j >= 0 && isspace(cmd[j]); j--) {
        cmd[j] = '\0';
    }

    // split into command and arguments
    argc = 0;
    char *t;
    
    for (int i=0; i < MAXARGS; i++) {
        argv[i] = NULL;
    }    
    t = strtok(s, " ");
    while (t && argc < 10) {
        argv[argc++] = t;
        t = strtok(NULL, " ");
    }

    return;
}