source: mainline/uspace/app/bdsh/cmds/modules/ls/ls.c@ a716a75

/* Copyright (c) 2008, Tim Post <tinkertim@gmail.com>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * Neither the name of the original program's authors nor the names of its
 * contributors may be used to endorse or promote products derived from this
 * software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

/* NOTE:
 * This is a bit of an ugly hack, working around the absence of fstat / etc.
 * As more stuff is completed and exposed in libc, this will improve */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <dirent.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <str.h>

#include "errors.h"
#include "config.h"
#include "util.h"
#include "entry.h"
#include "ls.h"
#include "cmds.h"

static const char *cmdname = "ls";

/** Sort array of files/directories
 *
 * Sort an array containing files and directories,
 * in alphabetical order, with files first.
 *
 * @param d                     Current directory.
 * @param tab           Array of file/directories to sort.
 * @param nbdirs        Number of elements.
 *
 */
static void ls_sort_dir(const char *d, char ** tab, int nbdirs)
{
        int i = 0;
        int j = 0;
        int min = 0;
        int rc;
        char * buff1 = NULL;
        char * buff2 = NULL;
        char * tmp = NULL;
        struct stat s1;
        struct stat s2;
        
        buff1 = (char *)malloc(PATH_MAX);
        if (NULL == buff1) {
                cli_error(CL_ENOMEM, "ls: failed to scan %s", d);
                return;
        }
        
        buff2 = (char *)malloc(PATH_MAX);
        if (NULL == buff2) {
                cli_error(CL_ENOMEM, "ls: failed to scan %s", d);
                return;
        }
        
        for(i=0;i<nbdirs;i++) {
                min = i;
                
                for(j=i;j<nbdirs;j++) {
                        memset(buff1, 0, sizeof(buff1));
                        memset(buff2, 0, sizeof(buff2));
                        snprintf(buff1, PATH_MAX - 1, "%s/%s", d, tab[min]);
                        snprintf(buff2, PATH_MAX - 1, "%s/%s", d, tab[j]);
                        
                        rc = stat(buff1, &s1);
                        if (rc != 0) {
                                printf("ls: skipping bogus node %s\n", buff1);
                                printf("rc=%d\n", rc);
                                return;
                        }
                        
                        rc = stat(buff2, &s2);
                        if (rc != 0) {
                                printf("ls: skipping bogus node %s\n", buff2);
                                printf("rc=%d\n", rc);
                                return;
                        }
                        
                        if ((s2.is_file && s1.is_directory)
                                || (((s2.is_file && s1.is_file)
                                || (s2.is_directory && s1.is_directory))
                                && str_cmp(tab[min], tab[j]) > 0))
                            min = j;
                }
                
                tmp = tab[i];
                tab[i] = tab[min];
                tab[min] = tmp;
        }
        
        free(buff1);
        free(buff2);
        
        return;
}

/** Scan a directory.
 *
 * Scan the content of a directory and print it.
 *
 * @param d             Name of the directory.
 * @param dirp  Directory stream.
 *
 */
static void ls_scan_dir(const char *d, DIR *dirp)
{
        int alloc_blocks = 20;
        int i = 0;
        int nbdirs = 0;
        char * buff = NULL;
        char ** tmp = NULL;
        char ** tosort = NULL;
        struct dirent * dp = NULL;

        if (! dirp)
                return;

        buff = (char *)malloc(PATH_MAX);
        if (NULL == buff) {
                cli_error(CL_ENOMEM, "ls: failed to scan %s", d);
                return;
        }
        
        tosort = (char **)malloc(alloc_blocks*sizeof(char *));
        if (NULL == tosort) {
                cli_error(CL_ENOMEM, "ls: failed to scan %s", d);
                return;
        }
        memset(tosort, 0, sizeof(tosort));
        
        while ((dp = readdir(dirp))) {
                nbdirs++;
                
                if (nbdirs > alloc_blocks) {
                        alloc_blocks += alloc_blocks;
                        
                        tmp = (char **)realloc(tosort, (alloc_blocks)*sizeof(char *));
                        if (NULL == tmp) {
                                cli_error(CL_ENOMEM, "ls: failed to scan %s", d);
                                return;
                        }
                        
                        tosort = tmp;
                }
                
                tosort[nbdirs-1] = (char *)malloc(str_length(dp->d_name)+1);
                if (NULL == tosort[nbdirs-1]) {
                                cli_error(CL_ENOMEM, "ls: failed to scan %s", d);
                                return;
                }
                memset(tosort[nbdirs-1], 0, str_length(dp->d_name)+1);
                
                str_cpy(tosort[nbdirs-1], str_length(dp->d_name)+1, dp->d_name);
        }
        
        ls_sort_dir(d, tosort, nbdirs);
        
        for(i=0;i<nbdirs;i++) {
                memset(buff, 0, sizeof(buff));
                /* Don't worry if inserting a double slash, this will be fixed by
                 * absolutize() later with subsequent calls to open() or readdir() */
                snprintf(buff, PATH_MAX - 1, "%s/%s", d, tosort[i]);
                ls_print(tosort[i], buff);
                free(tosort[i]);
        }
        
        free(tosort);
        free(buff);

        return;
}

/* ls_print currently does nothing more than print the entry.
 * in the future, we will likely pass the absolute path, and
 * some sort of ls_options structure that controls how each
 * entry is printed and what is printed about it.
 *
 * Now we just print basic DOS style lists */

static void ls_print(const char *name, const char *pathname)
{
        struct stat s;
        int rc;

        rc = stat(pathname, &s);
        if (rc != 0) {
                /* Odd chance it was deleted from the time readdir() found it */
                printf("ls: skipping bogus node %s\n", pathname);
                printf("rc=%d\n", rc);
                return;
        }
        
        if (s.is_file)
                printf("%-40s\t%llu\n", name, (long long) s.size);
        else if (s.is_directory)
                printf("%-40s\t<dir>\n", name);
        else
                printf("%-40s\n", name);

        return;
}

void help_cmd_ls(unsigned int level)
{
        if (level == HELP_SHORT) {
                printf("`%s' lists files and directories.\n", cmdname);
        } else {
                help_cmd_ls(HELP_SHORT);
                printf("  `%s' [path], if no path is given the current "
                                "working directory is used.\n", cmdname);
        }

        return;
}

int cmd_ls(char **argv)
{
        unsigned int argc;
        struct stat s;
        char *buff;
        DIR *dirp;

        argc = cli_count_args(argv);

        buff = (char *) malloc(PATH_MAX);
        if (NULL == buff) {
                cli_error(CL_ENOMEM, "%s: ", cmdname);
                return CMD_FAILURE;
        }
        memset(buff, 0, sizeof(buff));

        if (argc == 1)
                getcwd(buff, PATH_MAX);
        else
                str_cpy(buff, PATH_MAX, argv[1]);

        if (stat(buff, &s)) {
                cli_error(CL_ENOENT, buff);
                free(buff);
                return CMD_FAILURE;
        }

        if (s.is_file) {
                ls_print(buff, buff);
        } else {
                dirp = opendir(buff);
                if (!dirp) {
                        /* May have been deleted between scoping it and opening it */
                        cli_error(CL_EFAIL, "Could not stat %s", buff);
                        free(buff);
                        return CMD_FAILURE;
                }
                ls_scan_dir(buff, dirp);
                closedir(dirp);
        }

        free(buff);

        return CMD_SUCCESS;
}