[syslinux] Syslinux search for config file

[Gert Hulselmans]

2012/8/30 Tomas M <tomas at slax.org>:
>>> I also tested 4.05, and it did NOT search the install directory if such
>>>  directory is not in the "expected" list. Tomas also got the same result (as
>>>  he wrote in a previous email in this same thread).
>>
>> He stated such but without more data, I can't be certain he's not
>> encountering something that's already been resolved.
>
> I see symptoms as described by Ady Ady
> I install syslinux from windows, using syslinux.exe (32bit binary),
> which I got from syslinux 4.05 source distribution (there is the
> binary precompiled).
> # syslinux.exe -maf -d \slax\boot F:
>

I guess it is a bug in the windows version of the Syslinux installer:



In win/syslinux.c, the directory path will replace all / characters with \
(so -d /boot/blabla works the same as -d \boot\blabla):
================================================
    /* Move the file to the desired location */
    if (opt.directory) {
        char new_ldlinux_name[strlen(opt.directory) + 16];
        char *cp = new_ldlinux_name + 3;
        const char *sd;
        int slash = 1;

        new_ldlinux_name[0] = opt.device[0];
        new_ldlinux_name[1] = ':';
        new_ldlinux_name[2] = '\\';

        for (sd = opt.directory; *sd; sd++) {
            char c = *sd;

            if (c == '/' || c == '\\') {
                if (slash)
                    continue;
                c = '\\';
                slash = 1;
            } else {
                slash = 0;
            }

            *cp++ = c;
        }
================================================

In the syslinux_patch function of libinstaller/syslxmod.c:
================================================
    /* Poke in the base directory path */
    if (subdir) {
        int sublen = strlen(subdir) + 1;
        if (get_16_sl(&epa->dirlen) < sublen) {
            fprintf(stderr, "Subdirectory path too long... aborting
install!\n");
            exit(1);
        }
        memcpy_to_sl(ptr(boot_image, &epa->diroffset), subdir, sublen);
    }
================================================

The subdir name that is written to the extended patch area dir offset
(epa->diroffset)
contains always backslashes, when you run the Windows syslinux installer.
Probably Syslinux can't handle backslashes, when booted (in the configuration
files you also need to use forward slashes).


Run bootinfoscript: http://sourceforge.net/projects/bootinfoscript/

When you install Syslinux from linux, you will see something like this:

sdb1: __________________________________________________________________________

    File system:       vfat
    Boot sector type:  SYSLINUX 4.05 2011-12-09
    Boot sector info:  Syslinux looks at sector 952269 of /dev/sdb1 for its
                       second stage. SYSLINUX is installed in the
                       /boot/syslinux2 directory. No errors found in the Boot
                       Parameter Block.



When you install Syslinux from Windows, I expect that you will see
something like this:

sdb1: __________________________________________________________________________

    File system:       vfat
    Boot sector type:  SYSLINUX 4.05 2011-12-09
    Boot sector info:  Syslinux looks at sector 952269 of /dev/sdb1 for its
                       second stage. SYSLINUX is installed in the
                       \boot\syslinux2 directory. No errors found in the Boot
                       Parameter Block.


> Probably you have some syslinux.cfg file or similar somewhere in the
> common paths. Please try with blank sdb media and only one directory
> "b" in the root

I installed Syslinux to a different directory in the past (from linux)
and it worked fine. I tried directories with dots and spaces.


- Gert Hulselmans