This repository has been archived on 2023-08-20. You can view files and clone it, but cannot push or open issues or pull requests.
yap-6.3/packages/clib/memfile.c
2011-03-10 11:05:53 +00:00

543 lines
13 KiB
C

/* $Id$
Part of SWI-Prolog
Author: Jan Wielemaker
E-mail: J.Wielemaker@uva.nl
WWW: http://www.swi-prolog.org
Copyright (C): 1985-2009, University of Amsterdam
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <SWI-Stream.h>
#include <SWI-Prolog.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <errno.h>
#include "error.h"
#define streq(s,q) (strcmp((s), (q)) == 0)
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Memory-files
make_memory_file(-Handle)
free_memory_file(+Handle)
open_memory_file(+Handle, +Mode, -Stream)
size_memory_file(+Handle, -Size)
memory_file_to_codes(+Handle, -Codes)
memory_file_to_atom(+Handle, -Atom)
atom_to_memory_file(+Atom, -Handle)
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
static functor_t FUNCTOR_memory_file1;
static atom_t ATOM_encoding;
static atom_t ATOM_unknown;
static atom_t ATOM_octet;
static atom_t ATOM_ascii;
static atom_t ATOM_iso_latin_1;
static atom_t ATOM_text;
static atom_t ATOM_utf8;
static atom_t ATOM_unicode_be;
static atom_t ATOM_unicode_le;
static atom_t ATOM_wchar_t;
static atom_t ATOM_read;
static atom_t ATOM_write;
static atom_t ATOM_free_on_close;
#define MEMFILE_MAGIC 0x5624a6b3L
#define NOSIZE ((size_t)-1)
typedef struct
{ long magic; /* MEMFILE_MAGIC */
IOENC encoding; /* encoding of the data */
int free_on_close; /* free if it is closed */
char *data; /* data of the file */
size_t data_size; /* byte-size of data */
size_t size; /* size in characters */
IOSTREAM *stream; /* Stream hanging onto it */
atom_t atom; /* Created from atom */
} memfile;
static int
unify_memfile(term_t handle, memfile *f)
{ return PL_unify_term(handle,
PL_FUNCTOR, FUNCTOR_memory_file1,
PL_POINTER, f);
}
static int
get_memfile(term_t handle, memfile **f)
{ if ( PL_is_functor(handle, FUNCTOR_memory_file1) )
{ term_t a = PL_new_term_ref();
void *ptr;
_PL_get_arg(1, handle, a);
if ( PL_get_pointer(a, &ptr) )
{ memfile *m = ptr;
if ( m->magic == MEMFILE_MAGIC )
{ *f = ptr;
return TRUE;
}
return pl_error(NULL, 0, NULL, ERR_EXISTENCE,
"memory_file", handle);
}
}
return pl_error(NULL, 0, NULL, ERR_ARGTYPE, 1,
handle, "memory_file");
}
static foreign_t
new_memory_file(term_t handle)
{ memfile *m = calloc(1, sizeof(*m));
if ( !m )
return pl_error(NULL, 0, NULL, ERR_ERRNO, errno,
"create", "memory_file", handle);
m->magic = MEMFILE_MAGIC;
m->encoding = ENC_UTF8;
m->data = 0;
m->size = 0;
if ( unify_memfile(handle, m) )
return TRUE;
m->magic = 0;
free(m);
return FALSE;
}
static int
destroy_memory_file(memfile *m)
{ if ( m->stream )
Sclose(m->stream);
if ( m->atom )
PL_unregister_atom(m->atom);
else if ( m->data )
Sfree(m->data); /* MS-Windows: malloc by other DLL! */
m->magic = 0;
free(m);
return TRUE;
}
static foreign_t
free_memory_file(term_t handle)
{ memfile *m;
if ( get_memfile(handle, &m) )
return destroy_memory_file(m);
return FALSE;
}
static void
closehook(void *closure)
{ memfile *m = closure;
m->stream = NULL;
if ( m->free_on_close )
destroy_memory_file(m);
}
static foreign_t
alreadyOpen(term_t handle, const char *op)
{ return pl_error(NULL, 0, "already open",
ERR_PERMISSION, handle, op, "memory_file");
}
static struct encname
{ IOENC code;
atom_t *name;
} encoding_names[] =
{ { ENC_UNKNOWN, &ATOM_unknown },
{ ENC_OCTET, &ATOM_octet },
{ ENC_ASCII, &ATOM_ascii },
{ ENC_ISO_LATIN_1, &ATOM_iso_latin_1 },
{ ENC_ANSI, &ATOM_text },
{ ENC_UTF8, &ATOM_utf8 },
{ ENC_UNICODE_BE, &ATOM_unicode_be },
{ ENC_UNICODE_LE, &ATOM_unicode_le },
{ ENC_WCHAR, &ATOM_wchar_t },
{ ENC_UNKNOWN, NULL },
};
IOENC
atom_to_encoding(atom_t a)
{ struct encname *en;
for(en=encoding_names; en->name; en++)
{ if ( *en->name == a )
return en->code;
}
return ENC_UNKNOWN;
}
static int
get_encoding(term_t t, IOENC *enc)
{ atom_t en;
if ( PL_get_atom(t, &en) )
{ IOENC encoding;
if ( (encoding = atom_to_encoding(en)) == ENC_UNKNOWN )
return pl_error(NULL, 0, NULL, ERR_DOMAIN, t, "encoding");
*enc = encoding;
return TRUE;
}
return pl_error(NULL, 0, NULL, ERR_TYPE, t, "encoding");
}
static foreign_t
open_memory_file4(term_t handle, term_t mode, term_t stream, term_t options)
{ memfile *m;
char *x;
atom_t iom;
IOSTREAM *fd;
IOENC encoding;
int free_on_close = FALSE;
if ( !get_memfile(handle, &m) )
return FALSE;
if ( m->stream )
return alreadyOpen(handle, "open");
if ( !PL_get_atom(mode, &iom) )
return pl_error("open_memory_file", 3, NULL, ERR_ARGTYPE, 2,
mode, "io_mode");
encoding = m->encoding;
if ( options )
{ term_t tail = PL_copy_term_ref(options);
term_t head = PL_new_term_ref();
while(PL_get_list(tail, head, tail))
{ int arity;
atom_t name;
if ( PL_get_name_arity(head, &name, &arity) && arity == 1 )
{ term_t arg = PL_new_term_ref();
_PL_get_arg(1, head, arg);
if ( name == ATOM_encoding )
{ if ( !get_encoding(arg, &encoding) )
return FALSE;
} else if ( name == ATOM_free_on_close )
{ if ( !PL_get_bool(arg, &free_on_close) )
return pl_error("open_memory_file", 4, NULL, ERR_TYPE,
arg, "boolean");
}
} else
return pl_error("open_memory_file", 4, NULL, ERR_TYPE, head, "option");
}
if ( !PL_get_nil(tail) )
return pl_error("open_memory_file", 4, NULL, ERR_TYPE, tail, "list");
}
if ( iom == ATOM_write )
{ x = "w";
if ( m->atom )
return pl_error("open_memory_file", 3, NULL, ERR_PERMISSION,
handle, "write", "memory_file");
if ( m->data )
{ Sfree(m->data);
m->data = NULL;
}
m->data_size = 0;
m->size = NOSIZE; /* don't know */
m->encoding = encoding;
} else if ( iom == ATOM_read )
{ x = "r";
m->free_on_close = free_on_close;
} else
{ return pl_error("open_memory_file", 3, NULL, ERR_DOMAIN,
mode, "io_mode");
}
if ( !(fd = Sopenmem(&m->data, &m->data_size, x)) )
return pl_error("open_memory_file", 3, NULL, ERR_ERRNO, errno,
"create", "memory_file", handle);
fd->close_hook = closehook;
fd->closure = m;
fd->encoding = encoding;
m->stream = fd;
return PL_unify_stream(stream, fd);
}
static foreign_t
open_memory_file(term_t handle, term_t mode, term_t stream)
{ return open_memory_file4(handle, mode, stream, 0);
}
static foreign_t
size_memory_file(term_t handle, term_t sizeh, term_t encoding)
{ memfile *m;
if ( get_memfile(handle, &m) )
{ if ( m->stream && !m->atom )
return alreadyOpen(handle, "size");
if ( m->data )
{ IOENC size_enc = m->encoding;
size_t size;
if ( encoding )
{ if ( !get_encoding(encoding, &size_enc) )
return FALSE;
} else
size_enc = m->encoding;
if ( m->size != NOSIZE && size_enc == m->encoding )
{ size = m->size;
} else
{ switch( size_enc )
{ case ENC_ISO_LATIN_1:
case ENC_OCTET:
size = m->data_size;
break;
case ENC_WCHAR:
size = m->data_size / sizeof(wchar_t);
break;
case ENC_UTF8:
size = PL_utf8_strlen(m->data, m->data_size);
break;
default:
assert(0);
return FALSE;
}
if ( size_enc == m->encoding )
m->size = size;
}
return PL_unify_int64(sizeh, size);
} else
{ return PL_unify_integer(sizeh, 0);
}
}
return FALSE;
}
static foreign_t
size_memory_file2(term_t handle, term_t size)
{ return size_memory_file(handle, size, 0);
}
static foreign_t
size_memory_file3(term_t handle, term_t size, term_t encoding)
{ return size_memory_file(handle, size, encoding);
}
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
utf8_position_memory_file(+MF, -Here, -Size)
Given MF is a UTF-8 encoded memory file, unify here with the
byte-position of the read-pointer and Size with the total size of the
memory file in bytes. This is a bit hacky predicate, but the information
is easily available at low cost, while it is very valuable for producing
answers in content-length computation of the HTTP server. See
http_wrapper.pl
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
static foreign_t
utf8_position(term_t handle, term_t here, term_t size)
{ memfile *m;
if ( !get_memfile(handle, &m) )
return FALSE;
if ( m->encoding != ENC_UTF8 )
return pl_error(NULL, 0, "no UTF-8 encoding",
ERR_PERMISSION, handle, "utf8_position", "memory_file");
if ( !PL_unify_integer(size, m->data_size) )
return FALSE;
if ( m->stream )
{ IOPOS *op = m->stream->position;
long p;
m->stream->position = NULL;
p = Stell(m->stream);
m->stream->position = op;
return PL_unify_integer(here, p);
} else
return PL_unify_integer(here, 0);
}
static foreign_t
atom_to_memory_file(term_t atom, term_t handle)
{ atom_t a;
if ( PL_get_atom(atom, &a) )
{ memfile *m = calloc(1, sizeof(*m));
if ( !m )
return pl_error(NULL, 0, NULL, ERR_ERRNO, errno, "create", "memory_file", handle);
m->atom = a;
PL_register_atom(m->atom);
m->magic = MEMFILE_MAGIC;
if ( (m->data = (char *)PL_atom_nchars(a, &m->size)) )
{ m->encoding = ENC_ISO_LATIN_1;
m->data_size = m->size;
} else if ( (m->data = (char *)PL_atom_wchars(a, &m->size)) )
{ m->encoding = ENC_WCHAR;
m->data_size = m->size * sizeof(wchar_t);
} else if ( PL_blob_data(a, &m->size, NULL) )
{ m->data = PL_blob_data(a, &m->data_size, NULL);
m->encoding = ENC_OCTET;
m->size = m->data_size;
}
if ( unify_memfile(handle, m) )
return TRUE;
else
{ PL_unregister_atom(m->atom);
m->magic = 0;
free(m);
return FALSE;
}
} else
{ return pl_error(NULL, 0, NULL, ERR_ARGTYPE, 1,
atom, "atom");
}
}
static foreign_t
memory_file_to_text(term_t handle, term_t atom, term_t encoding, int flags)
{ memfile *m;
if ( get_memfile(handle, &m) )
{ IOENC enc;
if ( encoding )
{ if ( !get_encoding(encoding, &enc) )
return FALSE;
} else
enc = m->encoding;
if ( m->stream )
return alreadyOpen(handle, "to_atom");
if ( m->data )
{ switch(enc)
{ case ENC_ISO_LATIN_1:
case ENC_OCTET:
return PL_unify_chars(atom, flags, m->data_size, m->data);
case ENC_WCHAR:
return PL_unify_wchars(atom, flags, m->data_size/sizeof(wchar_t), (pl_wchar_t*)m->data);
case ENC_UTF8:
return PL_unify_chars(atom, flags|REP_UTF8, m->data_size, m->data);
default:
assert(0);
}
} else
return PL_unify_chars(atom, flags, 0, "");
}
return FALSE;
}
static foreign_t
memory_file_to_atom2(term_t handle, term_t atom)
{ return memory_file_to_text(handle, atom, 0, PL_ATOM);
}
static foreign_t
memory_file_to_atom3(term_t handle, term_t atom, term_t encoding)
{ return memory_file_to_text(handle, atom, encoding, PL_ATOM);
}
static foreign_t
memory_file_to_codes2(term_t handle, term_t atom)
{ return memory_file_to_text(handle, atom, 0, PL_CODE_LIST);
}
static foreign_t
memory_file_to_codes3(term_t handle, term_t atom, term_t encoding)
{ return memory_file_to_text(handle, atom, encoding, PL_CODE_LIST);
}
#define MKATOM(n) ATOM_ ## n = PL_new_atom(#n);
install_t
install_memfile()
{ if ( PL_query(PL_QUERY_VERSION) <= 50505 )
{ PL_warning("Requires SWI-Prolog version 5.5.6 or later");
return;
}
FUNCTOR_memory_file1 = PL_new_functor(PL_new_atom("$memory_file"), 1);
MKATOM(encoding);
MKATOM(unknown);
MKATOM(octet);
MKATOM(ascii);
MKATOM(iso_latin_1);
MKATOM(text);
MKATOM(utf8);
MKATOM(unicode_be);
MKATOM(unicode_le);
MKATOM(wchar_t);
MKATOM(read);
MKATOM(write);
MKATOM(free_on_close);
PL_register_foreign("new_memory_file", 1, new_memory_file, 0);
PL_register_foreign("free_memory_file", 1, free_memory_file, 0);
PL_register_foreign("size_memory_file", 2, size_memory_file2, 0);
PL_register_foreign("size_memory_file", 3, size_memory_file3, 0);
PL_register_foreign("open_memory_file", 3, open_memory_file, 0);
PL_register_foreign("open_memory_file", 4, open_memory_file4, 0);
PL_register_foreign("atom_to_memory_file", 2, atom_to_memory_file, 0);
PL_register_foreign("memory_file_to_atom", 2, memory_file_to_atom2, 0);
PL_register_foreign("memory_file_to_codes", 2, memory_file_to_codes2,0);
PL_register_foreign("memory_file_to_atom", 3, memory_file_to_atom3, 0);
PL_register_foreign("memory_file_to_codes", 3, memory_file_to_codes3,0);
PL_register_foreign("utf8_position_memory_file", 3, utf8_position, 0);
}