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/*
\funcref{insert}{void insert(\params)}
{
{char} {*idname} {identifier to insert in symbols table}
}
{}
{xrealloc()}
{directive()}
{insert.c}
{
{\em insert()} is called from {\em directive()} when an {\em \#define}
directive is read.
Function {\em insert()} is passed the name of a redefined identifier by
the {\em idname} argument. The redefinition part is expected in the
lexical buffer {\em lexbuf}.
The definition is inserted by increasing the array of {\em DEFINED\_}
structures, pointed to by {\em defined}, by one element. Then, the {\em
ident} and {\em redef} fields of the newly created struct are assigned.
Inside the definition constructions like \texttt{\$\{IDENT\}} may be used.
If \texttt{IDENT} is a previously defined macro, its definition will replace
\texttt{\$\{IDENT\}}. In one single definition at most 100
replacements are allowed.
After this, the counter {\em ndefined} is increased.
}
*/
#include "icm-pp.h"
static char *replace_defines(char *txt)
{
char *ptr1 = txt;
size_t const max_replacements = 100;
size_t replacement = 0;
while ((ptr1 = strstr(ptr1, "${"))) /* find the opening characters */
{
int idx; /* index in the #define database */
char *ptr2 = strchr(ptr1, '}'); /* and the closing character */
char *newContents;
if (!ptr2) /* none found, then done */
break;
*ptr2 = 0; /* terminate the presumed ${IDENT} */
/* at final brace */
idx = finddef(ptr1 + 2); /* lookup the identifier */
if (idx == -1) /* unknown identifier: keep ${...} */
{
*ptr2 = '}'; /* restore the closing brace */
ptr1 = ptr2 + 1; /* continue beyond this ${...} */
continue;
}
if (++replacement > max_replacements)
error("%s: %d: too many replacements in #define definition",
filestack[filesp].n, filestack[filesp].l);
newContents =
malloc(
1 + /* ascii-Z */
ptr1 - txt + /* plus length of initial txt */
/* plus length of replacement text */
strlen(defined[idx].redef) +
strlen(ptr2 + 1) /* plus text beyond ${IDENT} */
);
*ptr1 = 0; /* cut-off text beyond initial text */
strcpy(newContents, txt); /* write initial text */
/* add replacement */
strcat(newContents, defined[idx].redef);
strcat(newContents, ptr2 + 1); /* add the tail */
/* ptr1 points into the new text */
ptr1 = newContents +(ptr1 - txt);
free(txt);
txt = newContents;
}
return txt;
}
void insert(char *idname)
{
defined = xrealloc(defined, (ndefined + 1) * sizeof(DEFINED_));
defined[ndefined].ident = xstrdup(idname);
defined[ndefined].redef = replace_defines(xstrdup(lexbuf.data));
/*
fprintf(stderr, "Inserted `%s' with definition `%s'\n",
defined[ndefined].ident,
defined[ndefined].redef);
*/
ndefined++;
}
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