hyung-hwan/hawk
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

enhanced sys::read() to accept the 4th parameter as an input end delimiter

Browse Source
This commit is contained in:
hyung-hwan 2020-09-14 11:28:57 +00:00
parent c15966a0f4
commit 2fe815e815
1 changed files with 84 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

86
hawk/lib/mod-sys.c
View File

@ -205,6 +205,7 @@ struct sys_list_data_t
hawk_ooch_t errmsg[256];
hawk_bch_t* readbuf;
hawk_oow_t readbuf_capa;
hawk_oow_t readbuf_len;
hawk_ooch_t skadbuf[2][256];
};
typedef struct sys_list_data_t sys_list_data_t;
@ -683,12 +684,19 @@ static int fnc_openfd (hawk_rtx_t* rtx, const hawk_fnc_info_t* fi)
}
/* sys::read(sck, buf[, limit, [, delim]]);
*
* [NOTE]
* If delim is specified, sys::read() may keep some residue data for subsequent calls.
* sys::recvfrom() discards the residue data if it is called after sys::read().
*/
static int fnc_read (hawk_rtx_t* rtx, const hawk_fnc_info_t* fi)
{
sys_list_t* sys_list;
sys_node_t* sys_node;
hawk_int_t rx;
hawk_int_t reqsize = 8192;
hawk_bci_t delim = HAWK_BCI_EOF;
sys_list = rtx_to_sys_list(rtx, fi);
sys_node = get_sys_list_node_with_arg(rtx, sys_list, hawk_rtx_getarg(rtx, 0), SYS_NODE_DATA_TYPE_FILE | SYS_NODE_DATA_TYPE_SCK, &rx);
@ -709,7 +717,44 @@ static int fnc_read (hawk_rtx_t* rtx, const hawk_fnc_info_t* fi)
sys_list->ctx.readbuf_capa = reqsize;
}
rx = read(sys_node->ctx.u.file.fd, sys_list->ctx.readbuf, reqsize);
if (hawk_rtx_getnargs(rtx) >= 4)
{
hawk_bch_t* str;
hawk_oow_t len;
hawk_val_t* a3 = hawk_rtx_getarg(rtx, 3);
str = hawk_rtx_getvalbcstr(rtx, a3, &len);
if (!str)
{
rx = copy_error_to_sys_list(rtx, sys_list);
goto done;
}
if (len >= 1) delim = str[0];
hawk_rtx_freevalbcstr (rtx, a3, str);
}
if (sys_list->ctx.readbuf_len > 0 && delim != HAWK_BCI_EOF)
{
/* the read buffer has some residue data and the delimiter has been specified */
hawk_int_t i;
for (i = 0; i < sys_list->ctx.readbuf_len; i++)
{
if (sys_list->ctx.readbuf[i] == delim)
{
/* the residue data contains the delimiter */
rx = i + 1;
goto make_val_1;
}
}
}
/* check the residue data is bigger than the maximum data size requested */
if (sys_list->ctx.readbuf_len >= reqsize) goto make_val_0;
/* invoke the read system call */
rx = read(sys_node->ctx.u.file.fd, &sys_list->ctx.readbuf[sys_list->ctx.readbuf_len], reqsize - sys_list->ctx.readbuf_len);
if (rx <= 0)
{
if (rx <= -1) rx = set_error_on_sys_list_with_errno(rtx, sys_list, HAWK_T("unable to read"));
@ -720,6 +765,27 @@ static int fnc_read (hawk_rtx_t* rtx, const hawk_fnc_info_t* fi)
hawk_val_t* sv;
int x;
sys_list->ctx.readbuf_len += rx;
make_val_0:
/* determine the data size to return */
rx = reqsize <= sys_list->ctx.readbuf_len? reqsize: sys_list->ctx.readbuf_len;
if (delim != HAWK_BCI_EOF)
{
/* if the delimiter is specified, check if the data size can be shortened
* by finding the delimiter */
hawk_int_t i;
for (i = 0; i < rx; i++)
{
if (sys_list->ctx.readbuf[i] == delim)
{
rx = i + 1;
break;
}
}
}
make_val_1:
sv = hawk_rtx_makembsvalwithbchars(rtx, sys_list->ctx.readbuf, rx);
if (!sv)
{
@ -727,6 +793,14 @@ static int fnc_read (hawk_rtx_t* rtx, const hawk_fnc_info_t* fi)
goto done;
}
if (rx < sys_list->ctx.readbuf_len)
{
HAWK_MEMMOVE (&sys_list->ctx.readbuf[0], &sys_list->ctx.readbuf[rx],
(sys_list->ctx.readbuf_len - rx) * HAWK_SIZEOF(hawk_bch_t));
sys_list->ctx.readbuf_len -= rx;
}
else sys_list->ctx.readbuf_len = 0;
hawk_rtx_refupval (rtx, sv);
x = hawk_rtx_setrefval(rtx, (hawk_val_ref_t*)hawk_rtx_getarg(rtx, 1), sv);
hawk_rtx_refdownval (rtx, sv);
@ -3991,6 +4065,9 @@ done:
return 0;
}
/*
* sys:recvfrom(x, buf [, reqsize[, fromaddr]])
*/
static int fnc_recvfrom (hawk_rtx_t* rtx, const hawk_fnc_info_t* fi)
{
sys_list_t* sys_list;
@ -4032,6 +4109,11 @@ static int fnc_recvfrom (hawk_rtx_t* rtx, const hawk_fnc_info_t* fi)
hawk_val_t* sv;
int x;
/* avoid conflict with mixed calls to sys::read() and sys::recvfrom().
* sys::recvfrom() discards residue data by sys::read() and it leaves
* no residue by itself. */
sys_list->ctx.readbuf_len = 0;
sv = hawk_rtx_makembsvalwithbchars(rtx, sys_list->ctx.readbuf, rx);
if (!sv)
{
@ -4810,7 +4892,7 @@ static fnctab_t fnctab[] =
{ HAWK_T("openlog"), { { 3, 3, HAWK_NULL }, fnc_openlog, 0 } },
{ HAWK_T("openmux"), { { 0, 0, HAWK_NULL }, fnc_openmux, 0 } },
{ HAWK_T("pipe"), { { 2, 3, HAWK_T("rrv") }, fnc_pipe, 0 } },
{ HAWK_T("read"), { { 2, 3, HAWK_T("vrv") }, fnc_read, 0 } },
{ HAWK_T("read"), { { 2, 4, HAWK_T("vrvv") }, fnc_read, 0 } },
{ HAWK_T("readdir"), { { 2, 2, HAWK_T("vr") }, fnc_readdir, 0 } },
{ HAWK_T("recvfrom"), { { 2, 4, HAWK_T("vrvr") }, fnc_recvfrom, 0 } },
{ HAWK_T("resetdir"), { { 2, 2, HAWK_NULL }, fnc_resetdir, 0 } },