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yap-6.3/os/mem.c

390 lines
10 KiB
C
Executable File

/*************************************************************************
* *
* YAP Prolog *
* *
* Yap Prolog was developed at NCCUP - Universidade do Porto *
* *
* Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997 *
* *
**************************************************************************
* *
* File: mem.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 !HAVE_FMEMOPEN || !defined(HAVE_FMEMOPEN)
#include "YapStreams.h"
#include "format.h"
int format_synch(int sno, int sno0, format_info *fg) {
int (*f_putc)(int, int);
const char *s;
int n;
if (sno == sno0) {
return sno;
}
f_putc = GLOBAL_Stream[sno0].stream_putc;
s = GLOBAL_Stream[sno].u.mem_string.buf;
n = GLOBAL_Stream[sno].u.mem_string.pos;
while (n--) {
f_putc(sno0, *s++);
}
GLOBAL_Stream[sno].u.mem_string.pos = 0;
GLOBAL_Stream[sno].linecount = 1;
GLOBAL_Stream[sno].linepos = 0;
GLOBAL_Stream[sno].charcount = 0;
GLOBAL_Stream[sno].vfs = NULL;
fg->lstart = 0;
fg->phys_start = 0;
fg->gapi = 0;
return sno;
}
// uses directly the buffer in the memory stream.
bool fill_pads(int sno, int sno0, int total, format_info *fg USES_REGS) {
int nfillers, fill_space, lfill_space, nchars;
int (*f_putc)(int, int);
const char *buf;
int phys_end;
f_putc = GLOBAL_Stream[sno0].stream_putc;
buf = GLOBAL_Stream[sno].u.mem_string.buf;
phys_end = GLOBAL_Stream[sno].u.mem_string.pos;
if (fg->gapi == 0) {
fg->gap[0].phys = phys_end;
fg->gap[0].filler = ' ';
fg->gapi = 1;
}
nchars = total - GLOBAL_Stream[sno].linepos;
if (nchars < 0)
nchars = 0; /* ignore */
nfillers = fg->gapi;
fill_space = nchars / nfillers;
lfill_space = nchars % nfillers;
int i = fg->phys_start;
gap_t *padi = fg->gap;
while (i < phys_end) {
if (i == padi->phys) {
int j;
for (j = 0; j < fill_space; j++)
f_putc(sno0, padi->filler);
padi++;
/* last gap??*/
if (padi - fg->gap == fg->gapi) {
for (j = 0; j < fill_space; j++)
f_putc(sno0, (padi - 1)->filler);
}
}
f_putc(sno0, buf[i++]);
}
// final gap
if (i == padi->phys) {
int j;
for (j = 0; j < fill_space + lfill_space; j++)
f_putc(sno0, padi->filler);
};
GLOBAL_Stream[sno].u.mem_string.pos = 0;
GLOBAL_Stream[sno].linecount = 1;
GLOBAL_Stream[sno].linepos += nchars;
GLOBAL_Stream[sno].charcount = 0;
GLOBAL_Stream[sno].vfs = NULL;
GLOBAL_Stream[sno].file = NULL;
fg->phys_start = 0;
fg->lstart = GLOBAL_Stream[sno].linepos;
fg->gapi = 0;
return true;
}
/* 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;
}
/* peek from memory */
int Yap_MemPeekc(int sno) {
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];
}
return ch;
}
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 new_src;
/* oops, we have reached an overflow */
Int new_max_size = s->u.mem_string.max_size + Yap_page_size;
char *newbuf;
if ((newbuf = (ADDR)realloc(s->u.mem_string.buf,
new_max_size * sizeof(char))) != NULL) {
new_src = MEM_BUF_MALLOC;
} 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;
}
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);
}
bool Yap_set_stream_to_buf(StreamDesc *st, const char *buf,
size_t nchars USES_REGS) {
FILE *f;
stream_flags_t flags;
st->file = f = NULL;
flags = Input_Stream_f | InMemory_Stream_f;
st->vfs = NULL;
Yap_initStream(st - GLOBAL_Stream, f, "buffer", "r", TermNil, LOCAL_encoding, flags, NULL);
// like any file stream.
/* 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; check new assets coode
Yap_DefaultStreamOps(st);
return true;
}
int Yap_open_buf_read_stream(const char *buf, size_t nchars, encoding_t *encp, memBufSource src , Atom name, Term uname) {
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;
st->file = f = NULL;
flags = Input_Stream_f | InMemory_Stream_f;
st->vfs = NULL;
st->name = name;
Yap_initStream(sno, f, Yap_LookupAtom("Memory Stream"),"wa", TermNil, encoding, flags, NULL);
// like any file stream.
/* 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;
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 i = push_text_stack();
const char *buf;
ti = Deref(ARG1);
buf = Yap_TextTermToText(ti PASS_REGS);
if (!buf) {
return false;
}
buf = pop_output_text_stack(i, buf);
sno = Yap_open_buf_read_stream(buf, strlen(buf) + 1, &LOCAL_encoding,
MEM_BUF_MALLOC, AtomNil, TermNil);
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 | FreeOnClose_Stream_f;
st->linepos = 0;
st->charcount = 0;
st->linecount = 1;
st->encoding = enc;
st->vfs = NULL;
st->file = NULL;
Yap_DefaultStreamOps(st);
st->nbuf = st->u.mem_string.buf = malloc(PLGETC_BUF_SIZE);
st->u.mem_string.src = MEM_BUF_MALLOC;
st->u.mem_string.max_size = PLGETC_BUF_SIZE - 1;
st->u.mem_string.pos = 0;
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) /* $open_mem_write_stream(-Stream) */
{
Term t;
int sno;
sno = Yap_OpenBufWriteStream(PASS_REGS1);
if (sno == -1)
return (PlIOError(SYSTEM_ERROR_INTERNAL, TermNil,
"new stream not available for open_mem_read_stream/1"));
t = Yap_MkStream(sno);
GLOBAL_Stream[sno].status |= InMemory_Stream_f;
return (Yap_unify(ARG1, t));
}
/**
* Yap_PeekMemwriteStream() shows the current buffer for a memory stream.
*
* @param sno, the in-memory stream
*
* @return temporary buffer, discarded by close and may be moved away
* by other writes..
*/
char *Yap_MemExportStreamPtr(int sno) {
GLOBAL_Stream[sno].u.mem_string.buf[GLOBAL_Stream[sno].u.mem_string.pos] =
'\0';
return GLOBAL_Stream[sno].u.mem_string.buf;
}
static Int peek_mem_write_stream(
USES_REGS1) { /* '$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;
ptr = GLOBAL_Stream[sno].u.mem_string.buf;
i = GLOBAL_Stream[sno].u.mem_string.pos;
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) {
st->stream_putc = MemPutc;
st->stream_getc = MemGetc;
}
bool Yap_CloseMemoryStream(int sno) {
if ((GLOBAL_Stream[sno].status & Output_Stream_f)) {
if (GLOBAL_Stream[sno].u.mem_string.src == MEM_BUF_MALLOC) {
free(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);
}
}
return true;
}
void Yap_InitMems(void) {
CACHE_REGS
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);
}
#endif