source: trunk/third/xmh/miscfuncs.c @ 9658

/* $XConsortium: miscfuncs.c,v 1.6 91/07/13 17:52:59 gildea Exp $ */

#include <X11/Xos.h>

#ifndef X_NOT_POSIX
#include <dirent.h>
#else
#ifdef SYSV
#include <dirent.h>
#else
#ifdef USG
#include <dirent.h>
#else
#include <sys/dir.h>
#ifndef dirent
#define dirent direct
#endif
#endif
#endif
#endif

char *malloc();
char *realloc();



#if defined(SYSV) && (defined(SYSV386) || defined(MOTOROLA))

/* These systems don't have the ftruncate() system call, so we emulate it.
 * This emulation can only shorten, not lengthen.
 * For convenience, we pass in the name of the file, even though the
 * real ftruncate doesn't.
 */

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>

#define CHUNKSIZE 1024

int ftruncate_emu(fd, length, name)
    int fd;
    off_t length;
    char *name;
{
    char            tmp_file[15];
    int             new_fid, bytes_left, i;
    unsigned char   buffer[CHUNKSIZE];
    struct stat     stat_val;

    /* Open a temp file. */
    sprintf(tmp_file, ".xmhtmp%d~", getpid());
    (void) unlink(tmp_file);
    new_fid = open(tmp_file, O_RDWR | O_CREAT);
    lseek(fd, (off_t)0, 0);
        
    /* Copy original file to temp file. */
    for (i = 0; i < length / CHUNKSIZE; i++) {
        if (read(fd, buffer, CHUNKSIZE) != CHUNKSIZE) {
            (void)fprintf(stderr, "xmh: read error in ftruncate emulation\n");
            return -1;
        }
        else if (write(new_fid, buffer, CHUNKSIZE) != CHUNKSIZE) {
            (void)fprintf(stderr, "xmh: write error in ftruncate emulation\n");
            return -1;
        }
    }
    bytes_left = length % CHUNKSIZE;
    if (read(fd, buffer, bytes_left) != bytes_left) {
        (void)fprintf(stderr, "xmh: read error in ftruncate() emulation\n");
        return -1;
    }
    else if (write(new_fid, buffer, bytes_left) != bytes_left) {
        (void)fprintf(stderr, "xmh: write error in ftruncate() emulation\n");
        return -1;
    }

    /* Set mode of temp file to that of original file. */
    (void) fstat(fd, &stat_val);
    (void) chmod(tmp_file, stat_val.st_mode);

    /* Close files, delete original, rename temp file to original. */
    (void) myclose(new_fid);
    (void) myclose(fd);
    (void) unlink(name);        /* remove original */
    (void) rename(tmp_file, name); /* rename temp file */

    /* If we weren't going to close the file right away in the one
       place this is called from, we'd have to do something like this:
    new_fid = myopen(name, O_RDWR, 0666);
    if (new_fid != fd) {
        dup2(new_fid, fd);
        close(new_fid);
    }
       but the file does get closed, so we don't bother. */

    return 0;
}
#endif /* SYSV variant that needs ftruncate emulation */


/*
**  This code is by Rich Salz (rsalz@bbn.com), and ported to SVR4
**  by David Elliott (dce@smsc.sony.com).  No copyrights were found
**  in the original.  Subsequently modified by Bob Scheifler.
*/

/* A convenient shorthand. */
typedef struct dirent    ENTRY;

/* Initial guess at directory size. */
#define INITIAL_SIZE    20

static int StrCmp(a, b)
    char **a, **b;
{
    return strcmp(*a, *b);
}

int
ScanDir(Name, List, Selector)
    char                  *Name;
    char                ***List;
    int                  (*Selector)();
{
    register char        **names;
    register ENTRY        *E;
    register DIR          *Dp;
    register int           i;
    register int           size;

    /* Get initial list space and open directory. */
    size = INITIAL_SIZE;
    if (!(names = (char **)malloc(size * sizeof(char *))) ||
        !(Dp = opendir(Name)))
        return(-1);

    /* Read entries in the directory. */
    for (i = 0; E = readdir(Dp); )
        if (!Selector || (*Selector)(E->d_name)) {
            /* User wants them all, or he wants this one. */
            if (++i >= size) {
                size <<= 1;
                names = (char**)realloc((char *)names, size * sizeof(char*));
                if (!names) {
                    closedir(Dp);
                    return(-1);
                }
            }

            /* Copy the entry. */
            if (!(names[i - 1] = (char *)malloc(strlen(E->d_name) + 1))) {
                closedir(Dp);
                return(-1);
            }
            (void)strcpy(names[i - 1], E->d_name);
        }

    /* Close things off. */
    names[i] = (char *)0;
    *List = names;
    closedir(Dp);

    /* Sort? */
    if (i)
        qsort((char *)names, i, sizeof(char *), StrCmp);

    return(i);
}