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Diffstat (limited to 'c')
-rw-r--r--c/lex.c112
-rw-r--r--c/lex.h3
2 files changed, 80 insertions, 35 deletions
diff --git a/c/lex.c b/c/lex.c
index ce73155..5ff30a2 100644
--- a/c/lex.c
+++ b/c/lex.c
@@ -412,6 +412,7 @@ static int
lex0(struct lexer *lx, struct token *tk)
{
int idx,q;
+ bool space = 0;
Begin:
idx = lx->chridx;
if (lx->chrbuf0+4 >= countof(lx->chrbuf))
@@ -434,6 +435,7 @@ Begin:
}
case ' ': case '\t': case '\f': case '\v': case '\r':
+ space = 1;
goto Begin;
break;
case '(': case ')': case ',': case ':':
@@ -484,6 +486,7 @@ Begin:
lx->chridx = lx->chridxbuf[lx->chrbuf0+1];
lx->chrbuf0 += 2;
lx->eof = lx->chridx >= lx->ndat;
+ space = 1;
goto Begin;
}
} while (++lx->chrbuf0+1 < countof(lx->chrbuf));
@@ -599,6 +602,7 @@ Begin:
fatal(&(struct span) {{ idx, lx->chridx - idx, lx->fileid }},
"unexpected character %'c at %d (%d)", c, idx, lx->idx);
End:
+ tk->space = space;
tk->span.sl.file = lx->fileid;
tk->span.sl.off = idx;
tk->span.sl.len = lx->chridx - idx;
@@ -626,13 +630,6 @@ tokequ(const struct token *a, const struct token *b)
return 1;
}
-static bool /* whitespace separating tokens? */
-wsseparated(const struct token *l, const struct token *r)
-{
- if (l->span.sl.file != r->span.sl.file) return 1;
- return l->span.sl.off + l->span.sl.len != r->span.sl.off;
-}
-
static vec_of(struct token) mtoksbuf, /* buffers for macro replacement list tokens */
mdyntoksbuf; /* for function-like macros after parameter substitution */
@@ -673,7 +670,7 @@ macroequ(const struct macro *a, const struct macro *b)
for (int i = 0; i < a->rl.n; ++i) {
if (!tokequ(&tka[i], &tkb[i]))
return 0;
- if (i > 0 && wsseparated(&tka[i-1], &tka[i]) != wsseparated(&tkb[i-1], &tkb[i]))
+ if (i > 0 && tka[i].space != tkb[i].space)
return 0;
}
return 1;
@@ -747,7 +744,7 @@ static struct macrostack {
struct span0 exspan;
int idx;
short macid; /* -1 for argument undergoing expansion */
- bool stop, dyn;
+ bool space : 1, stop : 1, dyn;
} mstk[1200];
static void NORETURN
@@ -803,21 +800,18 @@ ppskipline(struct lexer *lx)
static bool
tokpaste(struct lexer *lx, struct token *dst, const struct token *l, const struct token *r)
{
- memset(dst, 0, sizeof *dst);
- dst->span = l->span;
- if (dst->span.ex.file == r->span.ex.file && dst->span.ex.off < r->span.ex.off)
- joinspan(&dst->span.ex, r->span.ex);
+ int t;
if (isppident(*l) && (isppident(*r) || r->t == TKNUMLIT)) {
/* foo ## bar ; foo ## 123 */
- dst->t = TKIDENT;
+ t = TKIDENT;
} else if (l->t == TKNUMLIT && (isppident(*r) || r->t == TKNUMLIT)) {
/* 0x ## abc ; 213 ## 456 */
- dst->t = TKNUMLIT;
+ t = TKNUMLIT;
} else if (l->t && !r->t) {
- *dst = *l;
+ if (dst) *dst = *l;
return 1;
} else if (!l->t && r->t) {
- *dst = *r;
+ if (dst) *dst = *r;
return 1;
} else {
static const struct { char s[2]; char t; } tab[] = {
@@ -828,21 +822,33 @@ tokpaste(struct lexer *lx, struct token *dst, const struct token *l, const struc
{"%=", TKSETREM}, {"|=", TKSETIOR}, {"^=", TKSETXOR}, {"&=", TKSETAND},
{{TKSHL,'='}, TKSETSHL}, {{TKSHR,'='}, TKSETSHR}
};
- for (int i = 0; i < countof(tab); ++i)
- if (tab[i].s[0] == l->t && tab[i].s[1] == r->t)
- return dst->t = tab[i].t, 1;
+ for (int i = 0; i < countof(tab); ++i) {
+ if (tab[i].s[0] == l->t && tab[i].s[1] == r->t) {
+ if (dst) dst->t = tab[i].t;
+ return 1;
+ }
+ }
- error(&l->span, "pasting %'tk and %'tk does not form a valid preprocessing token", l, r);
- note(&r->span, "right-hand side");
+ if (dst) {
+ error(&l->span, "pasting %'tk and %'tk does not form a valid preprocessing token", l, r);
+ note(&r->span, "right-hand side");
+ }
return 0;
}
+ if (!dst) return 1;
char buf[200];
+ memset(dst, 0, sizeof *dst);
+ dst->span = l->span;
+ if (dst->span.ex.file == r->span.ex.file && dst->span.ex.off < r->span.ex.off)
+ joinspan(&dst->span.ex, r->span.ex);
+ dst->t = t;
dst->len = l->len + r->len;
char *s = (isppident(*dst) && dst->len + 1 < sizeof buf) ? buf : alloc(lx->tmparena, dst->len + 1, 1);
memcpy(s, l->s, l->len);
memcpy(s + l->len, r->s, r->len);
s[dst->len] = 0;
+ dst->space = l->space;
if (isppident(*dst)) {
dst->blue = 0;
dst->name = intern(s);
@@ -912,7 +918,7 @@ ppdefine(struct lexer *lx)
/* gather replacement list */
mac.rl.off = mtoksbuf.n;
for (int n = 0; lex0(lx, &tk) != '\n' && tk.t != TKEOF;) {
- if (!n && !wsseparated(&tk0, &tk))
+ if (n == 0 && !tk.space)
warn(&tk.span, "no whitespace after macro name");
struct token *prev = n ? &mtoksbuf.p[mtoksbuf.n-1] : NULL;
if (mac.fnlike && tk.t == TKIDENT) {
@@ -1038,6 +1044,7 @@ tryexpand(struct lexer *lx, struct token *tk)
}
}
+ struct macrostack *stkprev = lx->macstk;
if (mac->special && !mac->fnlike) {
mac->handler(lx, tk);
return EXPINL;
@@ -1090,8 +1097,12 @@ tryexpand(struct lexer *lx, struct token *tk)
pushmacstk(lx, &span, &(struct macrostack){
.rl = { .off = mac->rl.off, .n = mac->rl.n },
.macid = mac->id,
+ .space = tk->space,
});
}
+ if (lx->macstk != stkprev) {
+ lx->macstk->space = tk->space;
+ }
return EXPSTACK;
}
@@ -1108,7 +1119,13 @@ advancemacstk(struct lexer *lx, struct token *tk)
popmac(lx, 1);
return 0;
}
- *tk = stkgetrl(s)[s->idx++];
+ *tk = stkgetrl(s)[s->idx];
+ if (s->idx == 0) {
+ /* the first token of the replaced expansion gets its space from the
+ * context in which it is expanded */
+ tk->space = s->space;
+ }
+ ++s->idx;
assert(tk->t && tk->t != TKEOF);
tk->span.ex = s->exspan;
return tryexpand(lx, tk) != EXPSTACK;
@@ -1133,7 +1150,14 @@ expandfnmacro(struct lexer *lx, struct span *span, internstr mname, struct macro
cur = i = bal = len = narg = 0;
for (struct macrostack *s = lx->macstk;;) {
- if (!s) do lex0(lx, &tk); while (tk.t == '\n');
+ if (!s) {
+ bool nl = 0;
+ for (;; nl = 1) {
+ lex0(lx, &tk);
+ if (tk.t != '\n') break;
+ }
+ tk.space |= nl;
+ }
else {
tk = s->idx < s->rl.n ? stkgetrl(s)[s->idx++] : (struct token){TKEOF};
}
@@ -1226,7 +1250,7 @@ expandfnmacro(struct lexer *lx, struct span *span, internstr mname, struct macro
.macid = mac->id,
});
} else if (mac->nparam > 0) { /* make new rlist with args replaced */
- bool vaoptskip = 0;
+ bool vaoptskip = 0, spacepad = 0;
int vaoptbal = 0;
uint off = mdyntoksbuf.n;
for (int i = 0; i < mac->rl.n; ++i) {
@@ -1243,6 +1267,7 @@ expandfnmacro(struct lexer *lx, struct span *span, internstr mname, struct macro
if (tki->t == TKPPCAT && i > 0 && i < mac->rl.n-1) { /* concatenation */
const struct token *lhs = tki-1,
*rhs = tki+1;
+ bool space = lhs->space | spacepad;
if (lhs->t == ',' && mac->variadic
&& rhs->t == TKPPMACARG && rhs->argidx == mac->nparam-1) {
/* handle GNU extension: ', ## __VA_ARGS__' */
@@ -1252,6 +1277,7 @@ expandfnmacro(struct lexer *lx, struct span *span, internstr mname, struct macro
--mdyntoksbuf.n;
} else { /* otherwise put comma and substitute vaargs */
vpushn(&mdyntoksbuf, argsbuf.p+arg->idx2, arg->n2);
+ mdyntoksbuf.p[mdyntoksbuf.n - arg->n2].space |= rhs->space | tk.space;
}
++i; /* we already handled rhs (__VA_ARGS__) */
continue;
@@ -1263,6 +1289,7 @@ expandfnmacro(struct lexer *lx, struct span *span, internstr mname, struct macro
} else if (lhs->t == TKPPMACARG) {
arg = &args[lhs->argidx];
lhs = arg->n ? &argsbuf.p[arg->idx + arg->n-1] : NULL;
+ if (lhs && arg->n > 1) space |= lhs->space;
} else {
--mdyntoksbuf.n;
}
@@ -1273,15 +1300,17 @@ expandfnmacro(struct lexer *lx, struct span *span, internstr mname, struct macro
++i;
}
if (!lhs && !rhs) continue;
+ spacepad = 0;
if (!lhs) vpush(&mdyntoksbuf, *rhs);
else if (!rhs) vpush(&mdyntoksbuf, *lhs);
else {
struct token new;
if (tokpaste(lx, &new, lhs, rhs)) {
new.span.sl = tki->span.sl;
- vpush(&mdyntoksbuf, new);
}
+ vpush(&mdyntoksbuf, new);
}
+ mdyntoksbuf.p[mdyntoksbuf.n-1].space = space;
} else if (tki->t != TKPPMACARG && tki->t != TKPPMACSTR) { /* regular token */
if (tki->t == TKIDENT && mac->variadic) {
/* handle GNUC __VA_OPT__(...) */
@@ -1302,21 +1331,34 @@ expandfnmacro(struct lexer *lx, struct span *span, internstr mname, struct macro
}
}
vpush(&mdyntoksbuf, *tki);
+ mdyntoksbuf.p[mdyntoksbuf.n-1].space |= spacepad;
+ spacepad = 0;
} else if (tki->t == TKPPMACARG) {
arg = &args[tki->argidx];
- if (arg->n == 0) continue;
+ if (arg->n == 0) {
+ spacepad = 1;
+ continue;
+ }
struct token *rl = argsbuf.p + arg->idx2;
int n = arg->n2;
+ bool skipfirst = 0;
if (i > 0 && tki[-1].t == TKPPCAT) {
/* skip first unexpanded token, was pasted */
rl += arg->nfirstx;
n -= arg->nfirstx;
+ skipfirst = 1;
}
if (i < mac->rl.n-2 && tki[1].t == TKPPCAT) {
/* skip last unexpanded token, will be pasted */
n -= arg->nlastx;
}
- if (n > 0) vpushn(&mdyntoksbuf, rl, n);
+ if (n > 0) {
+ vpushn(&mdyntoksbuf, rl, n);
+ if (!skipfirst)
+ /* the first token of the expanded body gets its space from the replacement list */
+ mdyntoksbuf.p[mdyntoksbuf.n - n].space = tki->space | spacepad;
+ }
+ spacepad = 0;
} else { /* PPMACSTR */
char tmp[200];
struct wbuf buf = MEMBUF(tmp, sizeof tmp);
@@ -1329,7 +1371,7 @@ expandfnmacro(struct lexer *lx, struct span *span, internstr mname, struct macro
Redo:
for (int i = 0; i < arg->n; ++i) {
struct token *tk = &argsbuf.p[arg->idx + i];
- if (i > 0 && wsseparated(tk-1, tk))
+ if (i > 0 && tk->space)
n += bfmt(&buf, " ");
n += bfmt(&buf, "%tk", tk);
}
@@ -1340,13 +1382,14 @@ expandfnmacro(struct lexer *lx, struct span *span, internstr mname, struct macro
memcpy(&buf, &new, sizeof buf);
goto Redo;
}
- struct token tk = {
+ vpush(&mdyntoksbuf, ((struct token) {
.t = TKSTRLIT,
.wide = 0,
+ .space = tki->space | spacepad,
.s = buf.buf != tmp ? buf.buf : alloccopy(lx->tmparena, buf.buf, buf.len, 1),
.len = buf.len-1,
- };
- vpush(&mdyntoksbuf, tk);
+ }));
+ spacepad = 0;
}
}
uint n = mdyntoksbuf.n - off;
@@ -2379,7 +2422,8 @@ lexerdump(struct lexer *lx, struct wbuf *out)
line = tkline;
col = 1;
lexerfreetemps(lx);
- } else if (prev.t && wsseparated(&prev, &tok)) {
+ } else if (prev.t && (tok.space || tokpaste(lx, NULL, &prev, &tok))) {
+ /* preserve whitespace & paste avoidance */
ioputc(out, ' ');
++col;
}
diff --git a/c/lex.h b/c/lex.h
index 35cf77d..e70bc78 100644
--- a/c/lex.h
+++ b/c/lex.h
@@ -57,7 +57,8 @@ struct token {
blue : 1, /* preprocessor token painted blue */
extwarn : 1; /* warn this keyword token is an extension */
uchar wide : 2, /* for CHRLIT & STRLIT; 1 -> 16bit, 2 -> 32bit */
- wideuni : 1; /* ditto, 0 -> 'L', 1 -> 'u'/'U' (C11) */
+ wideuni : 1, /* ditto, 0 -> 'L', 1 -> 'u'/'U' (C11) */
+ space : 1; /* preceded by whitespace? */
union {
uint len;
ushort argidx;
generated by cgit v1.2.3 (git 2.39.1) at 2026-05-02 05:42:53 +0000