/*
* In-line data blocks are implemented as a here-document:
* $FOO << EOD
* data line 1
* data line 2
* ...
* EOD
*
* The data block name must begin with $ followed by a letter.
* The string EOD is arbitrary; lines of data will be read from the input stream
* until the leading characters on the line match the given character string.
* No attempt is made to parse the data at the time it is read in.
*/
void
datablock_command()
{
FILE *fin;
char *name, *eod;
int nlines;
int nsize = 4;
struct udvt_entry *datablock;
char dataline[MAX_LINE_LEN+1];
if (!isletter(c_token+1))
int_error(c_token, "illegal datablock name");
/* Create or recycle a datablock with the requested name */
name = parse_datablock_name();
datablock = add_udv_by_name(name);
if (!datablock->udv_undef)
gpfree_datablock(&datablock->udv_value);
datablock->udv_undef = FALSE;
datablock->udv_value.type = DATABLOCK;
datablock->udv_value.v.data_array = NULL;
if (!equals(c_token, "<<") || !isletter(c_token+1))
int_error(c_token, "data block name must be followed by << EODmarker");
c_token++;
eod = gp_alloc(token[c_token].length +2, "datablock");
copy_str(&eod[0], c_token, token[c_token].length + 2);
c_token++;
/* Read in and store data lines until EOD */
fin = (lf_head == NULL) ? stdin : lf_head->fp;
if (!fin)
int_error(NO_CARET,"attempt to define data block from invalid context");
for (nlines = 0; fgets(dataline, MAX_LINE_LEN, fin); nlines++) {
int n;
if (!strncmp(eod, dataline, strlen(eod)))
break;
/* Allocate space for data lines plus at least 2 empty lines at the end. */
if (nlines >= nsize-4) {
nsize *= 2;
datablock->udv_value.v.data_array =
gp_realloc( datablock->udv_value.v.data_array,
nsize * sizeof(char *), "datablock");
memset(&datablock->udv_value.v.data_array[nlines], 0,
(nsize - nlines) * sizeof(char *));
}
/* Strip trailing newline character */
n = strlen(dataline);
if (n > 0 && dataline[n - 1] == '\n')
dataline[n - 1] = NUL;
datablock->udv_value.v.data_array[nlines] = gp_strdup(dataline);
}
inline_num += nlines + 1; /* Update position in input file */
free(eod);
return;
}
/* Used by plot2d/plot3d/fit:
* Parse an expression that may return a string or may return a constant or may
* be a dummy function using dummy variables x, y, ...
* If any dummy variables are present, set (*atptr) to point to an action table
* corresponding to the parsed expression, and return NULL.
* Otherwise evaluate the expression and return a string if there is one.
* The return value "str" and "*atptr" both point to locally-managed memory,
* which must not be freed by the caller!
*/
char*
string_or_express(struct at_type **atptr)
{
int i;
TBOOLEAN has_dummies;
static char* str = NULL;
free(str);
str = NULL;
if (atptr)
*atptr = NULL;
if (END_OF_COMMAND)
int_error(c_token, "expression expected");
/* parsing for datablocks */
if (equals(c_token,"$"))
return parse_datablock_name();
if (isstring(c_token)) {
str = try_to_get_string();
return str;
}
/* parse expression */
temp_at();
/* check if any dummy variables are used */
has_dummies = FALSE;
for (i = 0; i < at->a_count; i++) {
enum operators op_index = at->actions[i].index;
if ( op_index == PUSHD1 || op_index == PUSHD2 || op_index == PUSHD
|| op_index == SUM ) {
has_dummies = TRUE;
break;
}
}
if (!has_dummies) {
/* no dummy variables: evaluate expression */
struct value val;
evaluate_at(at, &val);
if (!undefined && val.type == STRING)
str = val.v.string_val;
}
/* prepare return */
if (atptr)
*atptr = at;
return str;
}
