X-Git-Url: https://git.draconx.ca/gitweb/cdecl99.git/blobdiff_plain/8b40c60072c0549d18afb1e19fa28ee18036957c..00514ec7f1070550a52651971bb6a5e36efbe4f0:/src/output.c

diff --git a/src/output.c b/src/output.c
index f691765..c0438e6 100644
--- a/src/output.c
+++ b/src/output.c
@@ -1,6 +1,6 @@
 /*
  *  Helper functions for outputting text.
- *  Copyright © 2011, 2021 Nick Bowler
+ *  Copyright © 2011, 2021, 2023 Nick Bowler
  *
  *  This program is free software: you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -22,76 +22,105 @@
 #include "cdecl.h"
 #include "cdecl-internal.h"
 
-size_t cdecl__advance_(char **buf, size_t *n, size_t amount)
+#include "parse.h"
+#include "specstr.h"
+
+size_t cdecl__advance(struct output_state *dst, size_t amount)
 {
-	if (amount >= *n) {
-		*n   = 0;
-		*buf = 0;
-	} else {
-		*buf += amount;
-		*n   -= amount;
-	}
+	size_t x = MIN(amount, dst->dstlen);
+
+	dst->dst    += x;
+	dst->dstlen -= x;
+	dst->accum  += amount;
 
 	return amount;
 }
 
-size_t cdecl__advance(char **buf, size_t *n, size_t amount)
+size_t cdecl__strlcpy(char *dst, const char *src, size_t dstlen)
 {
-	size_t ret, rc;
+	size_t srclen = strlen(src);
 
-	if (!amount)
-		return 0;
+	if (dstlen > 0) {
+		memcpy(dst, src, MIN(dstlen, srclen+1));
+		if (dstlen <= srclen)
+			dst[dstlen-1] = 0;
+	}
 
-	ret = cdecl__advance_(buf, n, amount);
-	rc = snprintf(*buf, *n, " ");
-	return ret + cdecl__advance_(buf, n, rc);
+	return srclen;
 }
 
-#include "specstr.h"
-
-static size_t explain_spec(char *buf, size_t n, struct cdecl_declspec *s)
+size_t cdecl__emit(struct output_state *dst, const char *src)
 {
-	const char *keyword = spec_string(s->type);
-
-	if (keyword[0] && s->ident)
-		return snprintf(buf, n, "%s %s", keyword, s->ident);
-	else if (s->ident)
-		return snprintf(buf, n, "%s", s->ident);
-	return snprintf(buf, n, "%s", keyword);
+	size_t rc = cdecl__strlcpy(dst->dst, src, dst->dstlen);
+	return cdecl__advance(dst, rc);
 }
 
 /*
- * Render a list of declaration specifiers.  Only the declaration specifiers
- * listed in mask, which is the bitwise OR of the desired specifier kinds, are
- * printed.
+ * 31 decimal digits is enough for values up to 2^102 - 1.
+ * 63 decimal digits is enough for values up to 2^209 - 1.
+ *
+ * We can't portably write numbers this large in preprocessor conditionals,
+ * but since the maximum values of unsigned integer types are always one
+ * less than a power of two, we can use a sequence of small shifts to infer
+ * the bounds.
+ *
+ * All known implementations have 64-bit uintmax_t.  Leave some headroom
+ * to support a possible future implementatons with 128-bit uintmax_t.
  */
-size_t cdecl__explain_specs(char *buf, size_t n, struct cdecl_declspec *s,
-                                                 unsigned mask)
+enum {
+#if (UINTMAX_MAX >> 27 >> 27 >> 26 >> 26) == 0
+	MAX_UINT_DIGITS = 31
+#elif (UINTMAX_MAX >> 27 >> 26 >> 26 >> 26 >> 26 >> 26 >> 26 >> 26) == 0
+	MAX_UINT_DIGITS = 63
+#else
+#	error UINTMAX_MAX is too large, please report a bug.
+#endif
+};
+
+size_t cdecl__emit_uint(struct output_state *dst, uintmax_t val)
 {
-	size_t ret = 0, rc = 0;
-
-	for (struct cdecl_declspec *c = s; c; c = c->next) {
-		switch (cdecl_spec_kind(c) & mask) {
-		case CDECL_SPEC_FUNC:
-		case CDECL_SPEC_STOR:
-		case CDECL_SPEC_QUAL:
-		case CDECL_SPEC_TYPE:
-			ret += cdecl__advance(&buf, &n, rc);
-			rc = explain_spec(buf, n, c);
-		}
+	char buf[MAX_UINT_DIGITS + 1], *p = &buf[sizeof buf];
+
+	*(--p) = 0;
+	while (val > 0) {
+		*(--p) = '0' + val % 10;
+		val /= 10;
 	}
 
-	return ret + rc;
+	return cdecl__emit(dst, p);
 }
 
-/* Renders the storage-class and function specifiers in canonical form. */
-size_t cdecl__explain_pre_specs(char *buf, size_t n, struct cdecl_declspec *s)
+static void explain_spec(struct output_state *dst, struct cdecl_declspec *s)
 {
-	return cdecl__explain_specs(buf, n, s, CDECL_SPEC_FUNC|CDECL_SPEC_STOR);
+	size_t rc;
+
+	rc = cdecl__emit(dst, spec_string(s->type));
+	if (s->ident) {
+		cdecl__emit(dst, " " + !rc);
+		cdecl__emit(dst, s->ident);
+	}
 }
 
-/* Renders the type qualifiers and type specifiers in canonical form. */
-size_t cdecl__explain_post_specs(char *buf, size_t n, struct cdecl_declspec *s)
+/*
+ * Render a list of declaration specifiers.  Only the declaration specifiers
+ * listed in mask, which is the bitwise OR of the desired specifier kinds, are
+ * printed.
+ */
+const char *cdecl__emit_specs(struct output_state *dst,
+                              struct cdecl_declspec *s,
+                              unsigned mask)
 {
-	return cdecl__explain_specs(buf, n, s, CDECL_SPEC_QUAL|CDECL_SPEC_TYPE);
+	const char *sep = " ";
+	int empty = 1;
+
+	for (; s; s = s->next) {
+		if (!(s->type & mask))
+			continue;
+
+		cdecl__emit(dst, sep + empty);
+		explain_spec(dst, s);
+		empty = 0;
+	}
+
+	return sep + empty;
 }