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yap-6.3/os/mem.c

380 lines
9.8 KiB
C

/*************************************************************************
* *
* YAP Prolog *
* *
* Yap Prolog was developed at NCCUP - Universidade do Porto *
* *
* Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997 *
* *
**************************************************************************
* *
* File: sockets.c *
* Last rev: 5/2/88 *
* mods: *
* comments: Input/Output C implemented predicates *
* *
*************************************************************************/
#ifdef SCCS
static char SccsId[] = "%W% %G%";
#endif
/*
* This file includes the definition of a socket related IO.
*
*/
#include "sysbits.h"
#if !MAY_READ
static int MemGetc(int);
/* read from memory */
static int MemGetc(int sno) {
register StreamDesc *s = &GLOBAL_Stream[sno];
Int ch;
int spos;
spos = s->u.mem_string.pos;
if (spos == s->u.mem_string.max_size) {
return -1;
} else {
ch = s->u.mem_string.buf[spos];
s->u.mem_string.pos = ++spos;
}
return ch;
}
#endif
#if !MAY_WRITE
static int MemPutc(int, int);
/* static */
static int MemPutc(int sno, int ch) {
StreamDesc *s = &GLOBAL_Stream[sno];
#if MAC || _MSC_VER
if (ch == 10) {
ch = '\n';
}
#endif
s->u.mem_string.buf[s->u.mem_string.pos++] = ch;
if (s->u.mem_string.pos >= s->u.mem_string.max_size - 8) {
int old_src = s->u.mem_string.src, new_src;
/* oops, we have reached an overflow */
Int new_max_size = s->u.mem_string.max_size + Yap_page_size;
char *newbuf;
if (old_src == MEM_BUF_CODE &&
(newbuf = Yap_AllocAtomSpace(new_max_size * sizeof(char))) != NULL) {
new_src = MEM_BUF_CODE;
#if HAVE_MEMMOVE
memmove((void *)newbuf, (void *)s->u.mem_string.buf,
(size_t)((s->u.mem_string.pos) * sizeof(char)));
#else
{
Int n = s->u.mem_string.pos;
char *to = newbuf;
char *from = s->u.mem_string.buf;
while (n-- >= 0) {
*to++ = *from++;
}
}
#endif
Yap_FreeAtomSpace(s->u.mem_string.buf);
#if !HAVE_SYSTEM_MALLOC
} else if ((newbuf = (ADDR)realloc(s->u.mem_string.buf,
new_max_size * sizeof(char))) != NULL) {
new_src = MEM_BUF_MALLOC;
#endif
} else {
if (GLOBAL_Stream[sno].u.mem_string.error_handler) {
CACHE_REGS
LOCAL_Error_Size = new_max_size * sizeof(char);
save_machine_regs();
longjmp(*(jmp_buf *)GLOBAL_Stream[sno].u.mem_string.error_handler, 1);
} else {
Yap_Error(RESOURCE_ERROR_HEAP, TermNil,
"YAP could not grow heap for writing to string");
}
return -1;
}
if (old_src == MEM_BUF_CODE) {
}
s->u.mem_string.buf = newbuf;
s->u.mem_string.max_size = new_max_size;
s->u.mem_string.src = new_src;
}
count_output_char(ch, s);
return ((int)ch);
}
#endif
int Yap_open_buf_read_stream(const char *buf, size_t nchars, encoding_t *encp,
memBufSource src) {
CACHE_REGS
int sno;
StreamDesc *st;
FILE *f;
encoding_t encoding;
stream_flags_t flags;
sno = GetFreeStreamD();
if (sno < 0)
return (PlIOError(RESOURCE_ERROR_MAX_STREAMS, TermNil,
"new stream not available for open_mem_read_stream/1"));
st = GLOBAL_Stream + sno;
if (encp)
encoding = *encp;
else
encoding = LOCAL_encoding;
#if MAY_READ
// like any file stream.
st->file = f = fmemopen((void *)buf, nchars, "r");
flags = Input_Stream_f | InMemory_Stream_f | Seekable_Stream_f;
#else
st->file = f = NULL;
flags = Input_Stream_f | InMemory_Stream_f;
#endif
Yap_initStream(sno, f, NULL, TermNil, encoding, flags, AtomRead);
// like any file stream.
#if !MAY_READ
/* currently these streams are not seekable */
st->status = Input_Stream_f | InMemory_Stream_f;
st->u.mem_string.pos = 0;
st->u.mem_string.buf = (char *)buf;
st->u.mem_string.max_size = nchars;
st->u.mem_string.error_handler = NULL;
st->u.mem_string.src = src;
#endif
Yap_DefaultStreamOps(st);
UNLOCK(st->streamlock);
return sno;
}
static Int
open_mem_read_stream(USES_REGS1) /* $open_mem_read_stream(+List,-Stream) */
{
Term t, ti;
int sno;
Int sl = 0, nchars = 0;
char *buf;
ti = Deref(ARG1);
while (ti != TermNil) {
if (IsVarTerm(ti)) {
Yap_Error(INSTANTIATION_ERROR, ti, "open_mem_read_stream");
return (FALSE);
} else if (!IsPairTerm(ti)) {
Yap_Error(TYPE_ERROR_LIST, ti, "open_mem_read_stream");
return (FALSE);
} else {
sl++;
ti = TailOfTerm(ti);
}
}
while ((buf = (char *)Yap_AllocAtomSpace((sl + 1) * sizeof(char))) == NULL) {
if (!Yap_growheap(FALSE, (sl + 1) * sizeof(char), NULL)) {
Yap_Error(RESOURCE_ERROR_HEAP, TermNil, LOCAL_ErrorMessage);
return (FALSE);
}
}
ti = Deref(ARG1);
while (ti != TermNil) {
Term ts = HeadOfTerm(ti);
if (IsVarTerm(ts)) {
Yap_Error(INSTANTIATION_ERROR, ARG1, "open_mem_read_stream");
return (FALSE);
} else if (!IsIntTerm(ts)) {
Yap_Error(TYPE_ERROR_INTEGER, ARG1, "open_mem_read_stream");
return (FALSE);
}
buf[nchars++] = IntOfTerm(ts);
ti = TailOfTerm(ti);
}
buf[nchars] = '\0';
sno = Yap_open_buf_read_stream(buf, nchars, &LOCAL_encoding, MEM_BUF_CODE);
t = Yap_MkStream(sno);
return (Yap_unify(ARG2, t));
}
// open a buffer for writing, currently just ignores buf and nchars.
int Yap_open_buf_write_stream(encoding_t enc, memBufSource src) {
CACHE_REGS
int sno;
StreamDesc *st;
sno = GetFreeStreamD();
if (sno < 0)
return -1;
st = GLOBAL_Stream + sno;
st->status = Output_Stream_f | InMemory_Stream_f;
st->linepos = 0;
st->charcount = 0;
st->linecount = 1;
st->encoding = enc;
Yap_DefaultStreamOps(st);
#if MAY_WRITE
#if HAVE_OPEN_MEMSTREAM
st->file = open_memstream(&st->nbuf, &st->nsize);
st->status |= Seekable_Stream_f;
#else
st->file = fmemopen((void *)buf, nchars, "w");
st->nsize = nchars;
st->nbuf = buf;
if (!st->nbuf) {
return -1;
}
#endif
#else
char buf[YAP_FILENAME_MAX + 1];
st->nbuf = buf;
st->u.mem_string.buf = buf;
st->u.mem_string.max_size = YAP_FILENAME_MAX;
#endif
UNLOCK(st->streamlock);
return sno;
}
int Yap_OpenBufWriteStream(USES_REGS1) {
return Yap_open_buf_write_stream(
GLOBAL_Stream[LOCAL_c_output_stream].encoding, 0);
}
static Int
open_mem_write_stream(USES_REGS1) /* $open_mem_write_stream(-Stream) */
{
Term t;
int sno;
sno = Yap_OpenBufWriteStream(PASS_REGS1);
if (sno == -1)
return (PlIOError(SYSTEM_ERROR_INTERNAL, TermNil,
"new stream not available for open_mem_read_stream/1"));
t = Yap_MkStream(sno);
return (Yap_unify(ARG1, t));
}
/**
* Yap_PeekMemwriteStream() shows the current buffer for a memory stream.
*
* @param sno, the in-memory stream
*
* @return temporary buffer, discarded by close and may be moved away
* by other writes..
*/
char *Yap_MemExportStreamPtr(int sno) {
#if MAY_WRITE
char *s;
if (fflush(GLOBAL_Stream[sno].file) == 0) {
s = GLOBAL_Stream[sno].nbuf;
return s;
}
return NULL;
#else
return GLOBAL_Stream[sno].u.mem_string.buf;
#endif
}
static Int peek_mem_write_stream(
USES_REGS1) { /* '$peek_mem_write_stream'(+GLOBAL_Stream,?S0,?S) */
Int sno =
Yap_CheckStream(ARG1, (Output_Stream_f | InMemory_Stream_f), "close/2");
Int i;
Term tf = ARG2;
CELL *HI;
const char *ptr;
if (sno < 0)
return (FALSE);
restart:
HI = HR;
#if MAY_WRITE
if (fflush(GLOBAL_Stream[sno].file) == 0) {
ptr = GLOBAL_Stream[sno].nbuf;
i = fseek(GLOBAL_Stream[sno].file, SEEK_END, 0);
}
#else
ptr = GLOBAL_Stream[sno].u.mem_string.buf;
i = GLOBAL_Stream[sno].u.mem_string.pos;
#endif
while (i > 0) {
--i;
tf = MkPairTerm(MkIntTerm(ptr[i]), tf);
if (HR + 1024 >= ASP) {
UNLOCK(GLOBAL_Stream[sno].streamlock);
HR = HI;
if (!Yap_gcl((ASP - HI) * sizeof(CELL), 3, ENV, Yap_gcP())) {
UNLOCK(GLOBAL_Stream[sno].streamlock);
Yap_Error(RESOURCE_ERROR_STACK, TermNil, LOCAL_ErrorMessage);
return (FALSE);
}
i = GLOBAL_Stream[sno].u.mem_string.pos;
tf = ARG2;
LOCK(GLOBAL_Stream[sno].streamlock);
goto restart;
}
}
UNLOCK(GLOBAL_Stream[sno].streamlock);
return (Yap_unify(ARG3, tf));
}
void Yap_MemOps(StreamDesc *st) {
#if MAY_WRITE
st->stream_putc = FilePutc;
#else
st->stream_putc = MemPutc;
#endif
#if MAY_READ
st->stream_getc = PlGetc;
#else
st->stream_getc = MemGetc;
#endif
}
bool Yap_CloseMemoryStream(int sno) {
if (!(GLOBAL_Stream[sno].status & Output_Stream_f)) {
#if MAY_WRITE
fflush(GLOBAL_Stream[sno].file);
fclose(GLOBAL_Stream[sno].file);
if (GLOBAL_Stream[sno].status & FreeOnClose_Stream_f)
free(GLOBAL_Stream[sno].nbuf);
#else
if (GLOBAL_Stream[sno].u.mem_string.src == MEM_BUF_CODE)
Yap_FreeAtomSpace(GLOBAL_Stream[sno].u.mem_string.buf);
else if (GLOBAL_Stream[sno].u.mem_string.src == MEM_BUF_MALLOC) {
free(GLOBAL_Stream[sno].u.mem_string.buf);
}
#endif
} else {
#if MAY_READ
fclose(GLOBAL_Stream[sno].file);
if (GLOBAL_Stream[sno].status & FreeOnClose_Stream_f)
free(GLOBAL_Stream[sno].nbuf);
#else
if (GLOBAL_Stream[sno].u.mem_string.src == MEM_BUF_CODE)
Yap_FreeAtomSpace(GLOBAL_Stream[sno].u.mem_string.buf);
else if (GLOBAL_Stream[sno].u.mem_string.src == MEM_BUF_MALLOC) {
free(GLOBAL_Stream[sno].u.mem_string.buf);
}
#endif
}
return true;
}
void Yap_InitMems(void) {
CACHE_REGS
Term cm = CurrentModule;
CurrentModule = CHARSIO_MODULE;
Yap_InitCPred("open_mem_read_stream", 2, open_mem_read_stream, SyncPredFlag);
Yap_InitCPred("open_mem_write_stream", 1, open_mem_write_stream,
SyncPredFlag);
Yap_InitCPred("peek_mem_write_stream", 3, peek_mem_write_stream,
SyncPredFlag);
CurrentModule = cm;
}