import the Slacker's QVM code base

1 files changed, 135 insertions, 0 deletions

diff --git a/src/tools/lcc/src/input.c b/src/tools/lcc/src/input.c
new file mode 100644
index 0000000..c2a084e
--- /dev/null
+++ b/src/tools/lcc/src/input.c
@@ -0,0 +1,135 @@
+#include "c.h"
+
+
+static void pragma(void);
+static void resynch(void);
+
+static int bsize;
+static unsigned char buffer[MAXLINE+1 + BUFSIZE+1];
+unsigned char *cp;	/* current input character */
+char *file;		/* current input file name */
+char *firstfile;	/* first input file */
+unsigned char *limit;	/* points to last character + 1 */
+char *line;		/* current line */
+int lineno;		/* line number of current line */
+
+void nextline(void) {
+	do {
+		if (cp >= limit) {
+			fillbuf();
+			if (cp >= limit)
+				cp = limit;
+			if (cp == limit)
+				return;
+		} else {
+			lineno++;
+			for (line = (char *)cp; *cp==' ' || *cp=='\t'; cp++)
+				;
+			if (*cp == '#') {
+				resynch();
+				nextline();
+			}
+		}
+	} while (*cp == '\n' && cp == limit);
+}
+void fillbuf(void) {
+	if (bsize == 0)
+		return;
+	if (cp >= limit)
+		cp = &buffer[MAXLINE+1];
+	else
+		{
+			int n = limit - cp;
+			unsigned char *s = &buffer[MAXLINE+1] - n;
+			assert(s >= buffer);
+			line = (char *)s - ((char *)cp - line);
+			while (cp < limit)
+				*s++ = *cp++;
+			cp = &buffer[MAXLINE+1] - n;
+		}
+	if (feof(stdin))
+		bsize = 0;
+	else
+		bsize = fread(&buffer[MAXLINE+1], 1, BUFSIZE, stdin);
+	if (bsize < 0) {
+		error("read error\n");
+		exit(EXIT_FAILURE);
+	}
+	limit = &buffer[MAXLINE+1+bsize];
+	*limit = '\n';
+}
+void input_init(int argc, char *argv[]) {
+	static int inited;
+
+	if (inited)
+		return;
+	inited = 1;
+	main_init(argc, argv);
+	limit = cp = &buffer[MAXLINE+1];
+	bsize = -1;
+	lineno = 0;
+	file = NULL;
+	fillbuf();
+	if (cp >= limit)
+		cp = limit;
+	nextline();
+}
+
+/* pragma - handle #pragma ref id... */
+static void pragma(void) {
+	if ((t = gettok()) == ID && strcmp(token, "ref") == 0)
+		for (;;) {
+			while (*cp == ' ' || *cp == '\t')
+				cp++;
+			if (*cp == '\n' || *cp == 0)
+				break;
+			if ((t = gettok()) == ID && tsym) {
+				tsym->ref++;
+				use(tsym, src);
+			}	
+		}
+}
+
+/* resynch - set line number/file name in # n [ "file" ] and #pragma ... */
+static void resynch(void) {
+	for (cp++; *cp == ' ' || *cp == '\t'; )
+		cp++;
+	if (limit - cp < MAXLINE)
+		fillbuf();
+	if (strncmp((char *)cp, "pragma", 6) == 0) {
+		cp += 6;
+		pragma();
+	} else if (*cp >= '0' && *cp <= '9') {
+	line:	for (lineno = 0; *cp >= '0' && *cp <= '9'; )
+			lineno = 10*lineno + *cp++ - '0';
+		lineno--;
+		while (*cp == ' ' || *cp == '\t')
+			cp++;
+		if (*cp == '"') {
+			file = (char *)++cp;
+			while (*cp && *cp != '"' && *cp != '\n')
+				cp++;
+			file = stringn(file, (char *)cp - file);
+			if (*cp == '\n')
+				warning("missing \" in preprocessor line\n");
+			if (firstfile == 0)
+				firstfile = file;
+		}
+	} else if (strncmp((char *)cp, "line", 4) == 0) {
+		for (cp += 4; *cp == ' ' || *cp == '\t'; )
+			cp++;
+		if (*cp >= '0' && *cp <= '9')
+			goto line;
+		if (Aflag >= 2)
+			warning("unrecognized control line\n");
+	} else if (Aflag >= 2 && *cp != '\n')
+		warning("unrecognized control line\n");
+	while (*cp)
+		if (*cp++ == '\n') {
+			if (cp == limit + 1)
+				nextline();
+			else
+				break;
+		}
+}
+