(* libc.def provides an interface to the C library functions.

Copyright (C) 2001-2024 Free Software Foundation, Inc.
Contributed by Gaius Mulley <gaius.mulley@southwales.ac.uk>.

This file is part of GNU Modula-2.

GNU Modula-2 is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.

GNU Modula-2 is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.

You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
<http://www.gnu.org/licenses/>.  *)

DEFINITION MODULE FOR "C" libc ;

FROM SYSTEM IMPORT ADDRESS, CSIZE_T, CSSIZE_T ;

EXPORT UNQUALIFIED time_t, timeb, tm, ptrToTM,
                   write, read,
                   system, abort,
                   malloc, free,
                   exit, isatty,
                   getenv, putenv, getpid,
                   dup, close, open, lseek,
                   readv, writev,
                   perror, creat,
                   getcwd, chown, strlen, strcpy, strncpy,
                   unlink, setenv,
                   memcpy, memset, memmove, printf, realloc,
                   rand, srand,
                   time, localtime, ftime,
                   shutdown, snprintf,
                   rename, setjmp, longjmp, atexit,
                   ttyname, sleep, execv ;


TYPE
   time_t = LONGINT ;

   ptrToTM = POINTER TO tm ;
   tm = RECORD
           tm_sec: INTEGER ;     (* Seconds.     [0-60] (1 leap second) *)
           tm_min: INTEGER ;     (* Minutes.     [0-59]   *)
           tm_hour: INTEGER ;    (* Hours.       [0-23]   *)
           tm_mday: INTEGER ;    (* Day.         [1-31]   *)
           tm_mon: INTEGER ;     (* Month.       [0-11]   *)
           tm_year: INTEGER ;    (* Year - 1900.          *)
           tm_wday: INTEGER ;    (* Day of week. [0-6]    *)
           tm_yday: INTEGER ;    (* Days in year.[0-365]  *)
           tm_isdst: INTEGER ;   (* DST.         [-1/0/1] *)
           tm_gmtoff: LONGINT ;  (* Seconds east of UTC.  *)
           tm_zone: ADDRESS ;    (* char * zone name      *)
        END ;

   timeb = RECORD
              time    : time_t ;
              millitm : SHORTCARD ;
              timezone: SHORTCARD ;
              dstflag : SHORTCARD ;
           END ;

   exitP = PROCEDURE () : INTEGER ;


(*
     ssize_t write (int d, void *buf, size_t nbytes)
*)

PROCEDURE write (d: INTEGER; buf: ADDRESS; nbytes: CSIZE_T) : [ CSSIZE_T ] ;


(*
     ssize_t read (int d, void *buf, size_t nbytes)
*)

PROCEDURE read (d: INTEGER; buf: ADDRESS; nbytes: CSIZE_T) : [ CSSIZE_T ] ;


(*
     int system(string)
     char *string;
*)

PROCEDURE system (a: ADDRESS) : [ INTEGER ] ;


(*
     abort - generate a fault

     abort() first closes all open files if possible, then sends
     an IOT signal to the process.  This signal usually results
     in termination with a core dump, which may be used for
     debugging.

     It is possible for abort() to return control if is caught or
     ignored, in which case the value returned is that of the
     kill(2V) system call.
*)

PROCEDURE abort <* noreturn *> ;


(*
     malloc - memory allocator.

     void *malloc(size_t size);

     malloc() returns a pointer to a block of at least size
     bytes, which is appropriately aligned.  If size is zero,
     malloc() returns a non-NULL pointer, but this pointer should
     not be dereferenced.
*)

PROCEDURE malloc (size: CSIZE_T) : ADDRESS ;


(*
     free - memory deallocator.

     free (void *ptr);

     free() releases a previously allocated block.  Its argument
     is a pointer to a block previously allocated by malloc,
     calloc, realloc, malloc, or memalign.
*)

PROCEDURE free (ptr: ADDRESS) ;


(*
     void *realloc (void *ptr, size_t size);

     realloc changes the size of the memory block pointed to
     by ptr to size bytes. The contents will be  unchanged  to
     the minimum of the old and new sizes; newly allocated memory
     will be uninitialized. If ptr is NIL, the call is
     equivalent  to malloc(size); if size is equal to zero, the
     call is equivalent to free(ptr). Unless ptr is NIL, it
     must have been returned by an earlier call to malloc(),
     realloc.
*)

PROCEDURE realloc (ptr: ADDRESS; size: CSIZE_T) : ADDRESS ;


(*
   isatty - does this descriptor refer to a terminal.
*)

PROCEDURE isatty (fd: INTEGER) : INTEGER ;


(*
   exit - returns control to the invoking process. Result, r, is
          returned.
*)

PROCEDURE exit (r: INTEGER) <* noreturn *> ;


(*
   getenv - returns the C string for the equivalent C environment
            variable.
*)

PROCEDURE getenv (s: ADDRESS) : ADDRESS ;


(*
   putenv - change or add an environment variable.
*)

PROCEDURE putenv (s: ADDRESS) : INTEGER ;


(*
   getpid - returns the UNIX process identification number.
*)

PROCEDURE getpid () : INTEGER ;


(*
   dup - duplicates the file descriptor, d.
*)

PROCEDURE dup (d: INTEGER) : INTEGER ;


(*
   close - closes the file descriptor, d.
*)

PROCEDURE close (d: INTEGER) : [ INTEGER ] ;


(*
   open - open the file, filename with flag and mode.
*)

PROCEDURE open (filename: ADDRESS; oflag: INTEGER; ...) : INTEGER ;


(*
   creat - creates a new file
*)

PROCEDURE creat (filename: ADDRESS; mode: CARDINAL) : INTEGER;


(*
   lseek - calls unix lseek:

           off_t lseek(int fildes, off_t offset, int whence);
*)

PROCEDURE lseek (fd: INTEGER; offset: CSSIZE_T; whence: INTEGER) : [ CSSIZE_T ] ;


(*
   perror - writes errno and string. (ARRAY OF CHAR is translated onto ADDRESS).
*)

PROCEDURE perror (string: ARRAY OF CHAR);


(*
   readv - reads an io vector of bytes.
*)

PROCEDURE readv (fd: INTEGER; v: ADDRESS; n: INTEGER) : [ INTEGER ] ;


(*
   writev - writes an io vector of bytes.
*)

PROCEDURE writev (fd: INTEGER; v: ADDRESS; n: INTEGER) : [ INTEGER ] ;


(*
   getcwd - copies the absolute pathname of the
            current working directory to the array pointed to by buf,
            which is of length size.

            If the current absolute path name would require a buffer
            longer than size elements, NULL is returned, and errno is
            set to ERANGE; an application should check for this error,
            and allocate a larger buffer if necessary.
*)

PROCEDURE getcwd (buf: ADDRESS; size: CSIZE_T) : ADDRESS ;


(*
   chown - The  owner  of  the  file  specified  by  path or by fd is
           changed.  Only the super-user may change the  owner  of  a
           file.   The  owner  of  a file may change the group of the
           file to any group of which that owner is  a  member.   The
           super-user may change the group arbitrarily.

           If  the owner or group is specified as -1, then that ID is
           not changed.

           On success, zero is returned.  On error, -1  is  returned,
           and errno is set appropriately.
*)

PROCEDURE chown (filename: ADDRESS; uid, gid: INTEGER) : [ INTEGER ] ;


(*
   strlen - returns the length of string, a.
*)

PROCEDURE strlen (a: ADDRESS) : CSIZE_T ;


(*
   strcpy - copies string, src, into, dest.
            It returns dest.
*)

PROCEDURE strcpy (dest, src: ADDRESS) : [ ADDRESS ] ;


(*
   strncpy - copies string, src, into, dest, copying at most, n, bytes.
             It returns dest.
*)

PROCEDURE strncpy (dest, src: ADDRESS; n: CARDINAL) : [ ADDRESS ] ;


(*
   unlink - removes file and returns 0 if successful.
*)

PROCEDURE unlink (file: ADDRESS) : [ INTEGER ] ;


(*
   memcpy - copy memory area

   SYNOPSIS

   #include <string.h>

   void *memcpy(void *dest, const void *src, size_t n);
   It returns dest.
*)

PROCEDURE memcpy (dest, src: ADDRESS; size: CSIZE_T) : [ ADDRESS ] ;


(*
   memset - fill memory with a constant byte

   SYNOPSIS

   #include <string.h>

   void *memset(void *s, int c, size_t n);
   It returns s.
*)

PROCEDURE memset (s: ADDRESS; c: INTEGER; size: CSIZE_T) : [ ADDRESS ] ;


(*
   memmove - copy memory areas which may overlap

   SYNOPSIS

   #include <string.h>

   void *memmove(void *dest, const void *src, size_t n);
   It returns dest.
*)

PROCEDURE memmove (dest, src: ADDRESS; size: CSIZE_T) : [ ADDRESS ] ;


(*
   int printf(const char *format, ...);
*)

PROCEDURE printf (format: ARRAY OF CHAR; ...) : [ INTEGER ] ;


(*
   int snprintf(char *str, size_t size, const char *format, ...);
*)

PROCEDURE snprintf (dest: ADDRESS; size: CSIZE_T;
                    format: ARRAY OF CHAR; ...) : [ INTEGER ] ;

(*
   setenv - sets environment variable, name, to value.
            It will overwrite an existing value if, overwrite,
            is true.  It returns 0 on success and -1 for an error.
*)

PROCEDURE setenv (name: ADDRESS; value: ADDRESS; overwrite: INTEGER) : [ INTEGER ] ;


(*
   srand - initialize the random number seed.
*)

PROCEDURE srand (seed: INTEGER) ;


(*
   rand - return a random integer.
*)

PROCEDURE rand () : INTEGER ;


(*
   time - returns a pointer to the time_t value. If, a,
          is not NIL then the libc value is copied into
          memory at address, a.
*)

PROCEDURE time (a: ADDRESS) : time_t ;


(*
   localtime - returns a pointer to the libc copy of the tm
               structure.
*)

PROCEDURE localtime (VAR t: time_t) : ADDRESS ;


(*
   ftime - return date and time.
*)

PROCEDURE ftime (VAR t: timeb) : [ INTEGER ] ;


(*
   shutdown - shutdown a socket, s.
              if how = 0, then no more reads are allowed.
              if how = 1, then no more writes are allowed.
              if how = 2, then mo more reads or writes are allowed.
*)

PROCEDURE shutdown (s: INTEGER; how: INTEGER) : [ INTEGER ] ;


(*
   rename - change the name or location of a file
*)

PROCEDURE rename (oldpath, newpath: ADDRESS) : [ INTEGER ] ;


(*
   setjmp - returns 0 if returning directly, and non-zero
            when returning from longjmp using the saved
            context.
*)

PROCEDURE setjmp (env: ADDRESS) : INTEGER ;


(*
   longjmp - restores the environment saved by the last call
             of setjmp with the corresponding env argument.
             After longjmp is completed, program execution
             continues as if the corresponding call of setjmp
             had just returned the value val.  The value of
             val must not be zero.
*)

PROCEDURE longjmp (env: ADDRESS; val: INTEGER) ;


(*
   atexit - execute, proc, when the function exit is called.
*)

PROCEDURE atexit (proc: exitP) : [ INTEGER ] ;


(*
   ttyname - returns a pointer to a string determining the ttyname.
*)

PROCEDURE ttyname (filedes: INTEGER) : ADDRESS ;


(*
   sleep - calling thread sleeps for seconds.
*)

PROCEDURE sleep (seconds: CARDINAL) : [ CARDINAL ] ;


(*
   execv - execute a file.
*)

PROCEDURE execv (pathname: ADDRESS; argv: ADDRESS) : [ INTEGER ] ;


END libc.