[cmds] Add ekermit to distribution images

[ghaerr]

Continuation of original contribution in #2554.

Builds ekermit and adds to compressed 1440k and larger images.

The original contribution displayed a large number of compiler warnings. This PR cleans some of the easier messages up, and includes a LOCALFLAGS modification to silence others. In general, it would be nice to fix the remaining issues so that the ELKS build produces less warnings, something we've worked hard on reducing for years.

@tyama501, thank you for the contribution. I'm unable to test, so I didn't try to fix further errors which might affect usability.
The current warning list is:

ia16-elf-gcc -mcmodel=small -melks-libc -mtune=i8086 -Wall -Os -mno-segment-relocation-stuff -fno-inline -fno-builtin-printf -fno-builtin-fprintf -Wextra -Wtype-limits -Wno-unused-parameter -Wno-sign-compare -Wno-empty-body -Wno-implicit-int -Wno-parentheses -DNO_LP -DELKS -Wno-unused-variable -Wno-unused-but-set-variable -Wno-pointer-sign -I/Users/greg/net/elks-gh/include -I/Users/greg/net/elks-gh/libc/include -I/Users/greg/net/elks-gh/elks/include -c -o main.o main.c
main.c: In function ‘main’:
main.c:388:14: warning: assignment from incompatible pointer type [-Wincompatible-pointer-types]
     k.dbf    = db ? dodebug : 0; /* for debugging */
              ^
ia16-elf-gcc -mcmodel=small -melks-libc -mtune=i8086 -Wall -Os -mno-segment-relocation-stuff -fno-inline -fno-builtin-printf -fno-builtin-fprintf -Wextra -Wtype-limits -Wno-unused-parameter -Wno-sign-compare -Wno-empty-body -Wno-implicit-int -Wno-parentheses -DNO_LP -DELKS -Wno-unused-variable -Wno-unused-but-set-variable -Wno-pointer-sign -I/Users/greg/net/elks-gh/include -I/Users/greg/net/elks-gh/libc/include -I/Users/greg/net/elks-gh/elks/include -c -o kermit.o kermit.c
kermit.c: In function ‘spar’:
kermit.c:1099:26: warning: ‘y’ may be used uninitialized in this function [-Wmaybe-uninitialized]
             x = xunchar(s[y+1]);
                          ^
kermit.c: In function ‘rpar’:
kermit.c:1168:9: warning: ‘b’ may be used uninitialized in this function [-Wmaybe-uninitialized]
  k->bct = b;
  ~~~~~~~^~~
kermit.c: In function ‘decode’:
kermit.c:1236:10: warning: ‘p’ may be used uninitialized in this function [-Wmaybe-uninitialized]
       *p = '\0';   /* terminate the string */
       ~~~^~~~~~
kermit.c: In function ‘gattr’:
kermit.c:1340:15: warning: ‘fsizek’ may be used uninitialized in this function [-Wmaybe-uninitialized]
     } else if (fsizek > -1L) {
               ^
kermit.c:1338:8: warning: ‘fsize’ may be used uninitialized in this function [-Wmaybe-uninitialized]
     if (fsize > -1L) {   /* Remember the file size */
        ^
kermit.c: In function ‘kermit’:
kermit.c:732:14: warning: ‘s’ may be used uninitialized in this function [-Wmaybe-uninitialized]
           rc = ack(k, k->r_seq, s);
           ~~~^~~~~~~~~~~~~~~~~~~~~
ia16-elf-gcc -mcmodel=small -melks-libc -mtune=i8086 -Wall -Os -mno-segment-relocation-stuff -fno-inline -fno-builtin-printf -fno-builtin-fprintf -Wextra -Wtype-limits -Wno-unused-parameter -Wno-sign-compare -Wno-empty-body -Wno-implicit-int -Wno-parentheses -DNO_LP -DELKS -Wno-unused-variable -Wno-unused-but-set-variable -Wno-pointer-sign -I/Users/greg/net/elks-gh/include -I/Users/greg/net/elks-gh/libc/include -I/Users/greg/net/elks-gh/elks/include -c -o elksio.o elksio.c
elksio.c: In function ‘fileinfo’:
elksio.c:513:19: warning: comparison is always true due to limited range of data type [-Wtype-limits]
      while (count < SCANSIZ && !isbinary) { /* Scan this much */
                   ^
In file included from elksio.c:59:0:
elksio.c: In function ‘readfile’:
debug.h:34:56: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
 #define debug(a,b,c,d) dodebug(a,(UCHAR *)b,(UCHAR *)c,(long)(d))
                                                        ^
elksio.c:581:5: note: in expansion of macro ‘debug’
     debug(DB_LOG,"readfile exit zinptr",0,k->zinptr);
     ^~~~~
ia16-elf-gcc -o ekermit -mcmodel=small -melks-libc -mtune=i8086 -Wall -Os -mno-segment-relocation-stuff -fno-inline -fno-builtin-printf -fno-builtin-fprintf main.o kermit.o elksio.o 

In some cases, the "maybe uninitialized" warnings can be removed by setting the variable to 0 on declaration, but one must be somewhat careful, as this could also be a warning of bad programming. I realize that e-kermit is ancient and it may be lots of work to fix all these. If so, that's ok, but thought to mention it.

[tyama501]

Hello @ghaerr ,

Thank you!

I wrote #2495 (comment) now.

I'm thinking to try compiling and add the host version when I have another time.
(unixio is just a sample, so I'm thinking to use elksio but compile it with host gcc)

[tyama501]

Hello @ghaerr

I see undef X_OK has been moved to kermit.h and it is removed from unixio.c.
It seems that the undef X_OK still remains in elksio.c but is there any reason for this?
If no, I will remove this on the next commit.

Thank you.

[ghaerr]

No, I didn't notice that in elksio.c, feel free to remove it and/or change things. The important item I noticed was that X_OK is defined to be 1 in unistd.h, but 0 in kermit.h, so one has to be careful when using the access system call, where X_OK means check execute permission.

I only notice one call to access which is in main.c, and that passes the constant 4 which is a bad idea. I presume, but have not tested, that R_OK is what's needed. These are the sorts of pitfalls one can encounter when porting ancient code.

Feel free to remove X_OK in elksio.c or anything else you need to do to get ekermit to work better. I only made these quick changes because I noticed them while taking a quick look at the source code, but no testing.

[tyama501]

Hello @ghaerr ,

Thank you!
Yes, I noticed the X_OK is redefined before but I didn't find the best way.
I will remove it in elksio.