Initial public snapshot

With code from Bill. Thanks Bill!

1 files changed, 238 insertions, 0 deletions

diff --git a/src/build/cmeta.c b/src/build/cmeta.c
new file mode 100644
index 0000000..b895253
--- /dev/null
+++ b/src/build/cmeta.c
@@ -0,0 +1,238 @@
+/*
+ * Copyright © 2021 Michael Smith <mikesmiffy128@gmail.com>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+ * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+ * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+ * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+ * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "../intdefs.h"
+#include "../os.h"
+
+/*
+ * This file does C metadata parsing/scraping for the build system. This
+ * facilitates tasks ranging from determining header dependencies to searching
+ * for certain magic macros (for example cvar/command declarations) to generate
+ * other code.
+ *
+ * It's a bit of a mess since it's kind of just hacked together for use at build
+ * time. Don't worry about it too much.
+ */
+
+// too lazy to write a C tokenizer at the moment, so let's just yoink some code
+// from a hacked-up copy of chibicc, a nice minimal C compiler with code that's
+// pretty easy to work with. it does leak memory by design, but build stuff is
+// all one-shot so that's fine.
+#include "../3p/chibicc/unicode.c"
+// type sentinels from type.c (don't bring in the rest of type.c because it
+// circularly depends on other stuff and we really only want tokenize here)
+Type *ty_void = &(Type){TY_VOID, 1, 1};
+Type *ty_bool = &(Type){TY_BOOL, 1, 1};
+Type *ty_char = &(Type){TY_CHAR, 1, 1};
+Type *ty_short = &(Type){TY_SHORT, 2, 2};
+Type *ty_int = &(Type){TY_INT, 4, 4};
+Type *ty_long = &(Type){TY_LONG, 8, 8};
+Type *ty_uchar = &(Type){TY_CHAR, 1, 1, true};
+Type *ty_ushort = &(Type){TY_SHORT, 2, 2, true};
+Type *ty_uint = &(Type){TY_INT, 4, 4, true};
+Type *ty_ulong = &(Type){TY_LONG, 8, 8, true};
+Type *ty_float = &(Type){TY_FLOAT, 4, 4};
+Type *ty_double = &(Type){TY_DOUBLE, 8, 8};
+Type *ty_ldouble = &(Type){TY_LDOUBLE, 16, 16};
+// inline just a couple more things, super lazy, but whatever
+static Type *new_type(TypeKind kind, int size, int align) {
+  Type *ty = calloc(1, sizeof(Type));
+  ty->kind = kind;
+  ty->size = size;
+  ty->align = align;
+  return ty;
+}
+Type *array_of(Type *base, int len) {
+  Type *ty = new_type(TY_ARRAY, base->size * len, base->align);
+  ty->base = base;
+  ty->array_len = len;
+  return ty;
+}
+#include "../3p/chibicc/hashmap.c"
+#include "../3p/chibicc/strings.c"
+#include "../3p/chibicc/tokenize.c"
+// one more copypaste from preprocess.c for #include <filename> and then I'm
+// done I promise
+static char *join_tokens(Token *tok, Token *end) {
+  int len = 1;
+  for (Token *t = tok; t != end && t->kind != TK_EOF; t = t->next) {
+    if (t != tok && t->has_space)
+      len++;
+    len += t->len;
+  }
+  char *buf = calloc(1, len);
+  int pos = 0;
+  for (Token *t = tok; t != end && t->kind != TK_EOF; t = t->next) {
+    if (t != tok && t->has_space)
+      buf[pos++] = ' ';
+    strncpy(buf + pos, t->loc, t->len);
+    pos += t->len;
+  }
+  buf[pos] = '\0';
+  return buf;
+}
+
+#ifdef _WIN32
+#include "../3p/openbsd/asprintf.c" // missing from libc; plonked here for now
+#endif
+
+static void die1(const char *s) {
+	fprintf(stderr, "cmeta: fatal: %s\n", s);
+	exit(100);
+}
+
+static char *readsource(const os_char *f) {
+	int fd = os_open(f, O_RDONLY);
+#ifndef _WIN32
+	if (fd == -1) die2("couldn't open ", f);
+#else
+	// TODO/FIXME/TEMP this is dumb and bad
+	if (fd == -1) { fprintf(stderr, "couldn't open %S", f); exit(100); }
+#endif
+	uint bufsz = 8192;
+	char *buf = malloc(bufsz);
+	if (!buf) die1("couldn't allocate memory");
+	int nread;
+	int off = 0;
+	while ((nread = read(fd, buf + off, bufsz - off)) > 0) {
+		off += nread;
+		if (off == bufsz) {
+			bufsz *= 2;
+			// somewhat arbitrary cutoff
+			if (bufsz == 1 << 30) die1("input file is too large");
+			buf = realloc(buf, bufsz);
+			if (!buf) die1("couldn't reallocate memory");
+		}
+	}
+	if (nread == -1) die1("couldn't read file");
+	buf[off] = 0;
+	close(fd);
+	return buf;
+}
+
+// as per cmeta.h this is totally opaque; it's actually just a Token in disguise
+struct cmeta;
+
+const struct cmeta *cmeta_loadfile(const os_char *f) {
+	char *buf = readsource(f);
+#ifdef _WIN32
+	char *realname = malloc(wcslen(f) + 1);
+	if (!realname) die1("couldn't allocate memory");
+	// XXX: being lazy about Unicode right now; a general purpose tool should
+	// implement WTF8 or something. SST itself doesn't have any unicode paths
+	// though, so don't really care as much.
+	*realname = *f;
+	for (const ushort *p = f + 1; p[-1]; ++p) realname[p - f] = *p;
+#else
+	const char *realname = f;
+#endif
+	return (const struct cmeta *)tokenize_buf(realname, buf);
+}
+
+// NOTE: we don't care about conditional includes, nor do we expand macros. We
+// just parse the minimum info to get what we need for SST. Also, there's not
+// too much in the way of syntax checking; if an error gets ignored the compiler
+// picks it anyway, and gives far better diagnostics.
+void cmeta_includes(const struct cmeta *cm,
+		void (*cb)(const char *f, bool issys, void *ctxt), void *ctxt) {
+	Token *tp = (Token *)cm;
+	if (!tp || !tp->next || !tp->next->next) return; // #, include, "string"
+	while (tp) {
+		if (!tp->at_bol || !equal(tp, "#")) { tp = tp->next; continue; }
+		if (!equal(tp->next, "include")) { tp = tp->next->next; continue; }
+		tp = tp->next->next;
+		if (!tp) break;
+		if (tp->at_bol) tp = tp->next;
+		if (!tp) break;
+		if (tp->kind == TK_STR) {
+			// include strings are a special case; they don't have \escapes.
+			char *copy = malloc(tp->len - 1);
+			if (!copy) die1("couldn't allocate memory");
+			memcpy(copy, tp->loc + 1, tp->len - 2);
+			copy[tp->len - 2] = '\0';
+			cb(copy, false, ctxt);
+			//free(copy); // ??????
+		}
+		else if (equal(tp, "<")) {
+			tp = tp->next;
+			if (!tp) break;
+			Token *end = tp;
+			while (!equal(end, ">")) {
+				end = end->next;
+				if (!end) return; // shouldn't happen in valid source obviously
+				if (end->at_bol) break; // ??????
+			}
+			char *joined = join_tokens(tp, end); // just use func from chibicc
+			cb(joined, true, ctxt);
+			//free(joined); // ??????
+		}
+		// get to the next line (standard allows extra tokens because)
+		while (!tp->at_bol) {
+			tp = tp->next;
+			if (!tp) return;
+		}
+	}
+}
+
+// AGAIN, NOTE: this doesn't *perfectly* match top level decls only in the event
+// that someone writes something weird, but we just don't really care because
+// we're not writing something weird. Don't write something weird!
+void cmeta_conmacros(const struct cmeta *cm, void (*cb)(const char *, bool)) {
+	Token *tp = (Token *)cm;
+	if (!tp || !tp->next || !tp->next->next) return; // DEF_xyz, (, name
+	while (tp) {
+		bool isplusminus = false, isvar = false;
+		if (equal(tp, "DEF_CCMD_PLUSMINUS")) isplusminus = true;
+		else if (equal(tp, "DEF_CVAR") || equal(tp, "DEF_CVAR_MIN") ||
+				equal(tp, "DEF_CVAR_MINMAX")) {
+			isvar = true;
+		}
+		else if (!equal(tp, "DEF_CCMD") && !equal(tp, "DEF_CCMD_HERE")) {
+			tp = tp->next; continue;
+		}
+		if (!equal(tp->next, "(")) { tp = tp->next->next; continue; }
+		tp = tp->next->next;
+		if (isplusminus) {
+			// XXX: this is stupid but whatever
+			char *plusname = malloc(sizeof("PLUS_") + tp->len);
+			if (!plusname) die1("couldn't allocate memory");
+			memcpy(plusname, "PLUS_", 5);
+			memcpy(plusname + sizeof("PLUS_") - 1, tp->loc, tp->len);
+			plusname[sizeof("PLUS_") - 1 + tp->len] = '\0';
+			cb(plusname, false);
+			char *minusname = malloc(sizeof("MINUS_") + tp->len);
+			if (!minusname) die1("couldn't allocate memory");
+			memcpy(minusname, "MINUS_", 5);
+			memcpy(minusname + sizeof("MINUS_") - 1, tp->loc, tp->len);
+			minusname[sizeof("MINUS_") - 1 + tp->len] = '\0';
+			cb(minusname, false);
+		}
+		else {
+			char *name = malloc(tp->len + 1);
+			if (!name) die1("couldn't allocate memory");
+			memcpy(name, tp->loc, tp->len);
+			name[tp->len] = '\0';
+			cb(name, isvar);
+		}
+		tp = tp->next;
+	}
+}
+
+// vi: sw=4 ts=4 noet tw=80 cc=80