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-rw-r--r--unproto/tok_io.c612
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diff --git a/unproto/tok_io.c b/unproto/tok_io.c
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+/*++
+/* NAME
+/* tok_io 3
+/* SUMMARY
+/* token I/O
+/* PACKAGE
+/* unproto
+/* SYNOPSIS
+/* #include "token.h"
+/*
+/* struct token *tok_get()
+/*
+/* void tok_flush(t)
+/* struct token *t;
+/*
+/* void tok_show(t)
+/* struct token *t;
+/*
+/* void tok_show_ch(t)
+/* struct token *t;
+/*
+/* void put_str(s)
+/* char *s;
+/*
+/* void put_ch(c)
+/* int c;
+/*
+/* void put_nl()
+/*
+/* char *in_path;
+/* int in_line;
+/* DESCRIPTION
+/* These functions read from stdin and write to stdout. The
+/* tokenizer keeps track of where the token appeared in the input
+/* stream; on output, this information is used to preserve correct
+/* line number information (even after lots of token lookahead or
+/* after function-header rewriting) so that diagnostics from the
+/* next compiler stage make sense.
+/*
+/* tok_get() reads the next token from standard input. It returns
+/* a null pointer when the end of input is reached.
+/*
+/* tok_show() displays the contents of a (possibly composite) token
+/* on the standard output.
+/*
+/* tok_show_ch() displays the contents of a single-character token
+/* on the standard output. The character should not be a newline.
+/*
+/* tok_flush() displays the contents of a (possibly composite) token
+/* on the standard output and makes it available for re-use.
+/*
+/* put_str() writes a null-terminated string to standard output.
+/* There should be no newline characters in the string argument.
+/*
+/* put_ch() writes one character to standard output. The character
+/* should not be a newline.
+/*
+/* put_nl() outputs a newline character and adjusts the program's idea of
+/* the current output line.
+/*
+/* The in_path and in_line variables contain the file name and
+/* line number of the most recently read token.
+/* BUGS
+/* The tokenizer is just good enough for the unproto filter.
+/* As a benefit, it is quite fast.
+/* AUTHOR(S)
+/* Wietse Venema
+/* Eindhoven University of Technology
+/* Department of Mathematics and Computer Science
+/* Den Dolech 2, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
+/* LAST MODIFICATION
+/* 92/01/15 21:52:59
+/* VERSION/RELEASE
+/* 1.3
+/*--*/
+
+static char io_sccsid[] = "@(#) tok_io.c 1.3 92/01/15 21:52:59";
+
+/* C library */
+
+#include <stdio.h>
+#include <ctype.h>
+
+extern char *strchr();
+extern char *malloc();
+extern char *realloc();
+extern char *strcpy();
+
+/* Application-specific stuff */
+
+#include "token.h"
+#include "vstring.h"
+#include "error.h"
+
+extern char *strsave(); /* XXX need include file */
+
+/* Stuff to keep track of original source file name and position */
+
+static char def_path[] = ""; /* default path name */
+
+char *in_path = def_path; /* current input file name */
+int in_line = 1; /* current input line number */
+
+static char *out_path = def_path; /* last name in output line control */
+static int out_line = 1; /* current output line number */
+int last_ch; /* type of last output */
+
+/* Forward declarations */
+
+static int read_quoted();
+static void read_comment();
+static int backslash_newline();
+static char *read_hex();
+static char *read_octal();
+static void fix_line_control();
+
+ /*
+ * Character input with one level of pushback. The INPUT() macro recursively
+ * strips backslash-newline pairs from the input stream. The UNPUT() macro
+ * should be used only for characters obtained through the INPUT() macro.
+ *
+ * After skipping a backslash-newline pair, the input line counter is not
+ * updated, and we continue with the same logical source line. We just
+ * update a counter with the number of backslash-newline sequences that must
+ * be accounted for (backslash_newline() updates the counter). At the end of
+ * the logical source line, an appropriate number of newline characters is
+ * pushed back (in tok_get()). I do not know how GCC handles this, but it
+ * seems to produce te same output.
+ *
+ * Because backslash_newline() recursively calls itself (through the INPUT()
+ * macro), we will run out of stack space, given a sufficiently long
+ * sequence of backslash-newline pairs.
+ */
+
+static char in_char = 0; /* push-back storage */
+static int in_flag = 0; /* pushback available */
+static int nl_compensate = 0; /* line continuation kluge */
+
+#define INPUT(c) (in_flag ? (in_flag = 0, c = in_char) : \
+ (c = getchar()) != '\\' ? c : \
+ (c = getchar()) != '\n' ? (ungetc(c, stdin), c = '\\') : \
+ (c = backslash_newline()))
+#define UNPUT(c) (in_flag = 1, in_char = c)
+
+/* Directives that should be ignored. */
+
+#ifdef IGNORE_DIRECTIVES
+
+static char *ignore_directives[] = {
+ IGNORE_DIRECTIVES,
+ 0,
+};
+
+#endif
+
+/* Modified string and ctype stuff. */
+
+#define STREQUAL(x,y) (*(x) == *(y) && strcmp((x),(y)) == 0)
+
+#define ISALNUM(c) (isalnum(c) || (c) == '_')
+#define ISALPHA(c) (isalpha(c) || (c) == '_')
+#define ISSPACE(c) (isspace(c) && c != '\n')
+#define ISDOT(c) (c == '.')
+#define ISHEX(c) (isdigit(c) || strchr("abcdefABCDEF", c) != 0)
+#define ISOCTAL(c) (isdigit(c) && (c) != '8' && (c) != '9')
+
+/* Collect all characters that satisfy one condition */
+
+#define COLLECT(v,c,cond) { \
+ register struct vstring *vs = v; \
+ register char *cp = vs->str; \
+ *cp++ = c; \
+ while (INPUT(c) != EOF) { \
+ if (cond) { \
+ if (VS_ADDCH(vs, cp, c) == 0) \
+ fatal("out of memory"); \
+ } else { \
+ UNPUT(c); \
+ break; \
+ } \
+ } \
+ *cp = 0; \
+ }
+
+/* Ensure that output line information is correct */
+
+#define CHECK_LINE_CONTROL(p,l) { if (out_path != (p) || out_line != (l)) \
+ fix_line_control((p),(l)); }
+
+/* do_control - parse control line */
+
+static int do_control()
+{
+ struct token *t;
+ int line;
+ char *path;
+
+ /* Make sure that the directive shows up in the right place. */
+
+ CHECK_LINE_CONTROL(in_path, in_line);
+
+ while (t = tok_get()) {
+ switch (t->tokno) {
+
+ case TOK_WSPACE:
+ /* Ignore blanks after "#" token. */
+ tok_free(t);
+ break;
+
+ case TOK_NUMBER:
+
+ /*
+ * Line control is of the form: number pathname junk. Since we
+ * have no idea what junk the preprocessor may generate, we copy
+ * all line control tokens to stdout.
+ */
+
+ put_str("# ");
+ line = atoi(t->vstr->str); /* extract line number */
+ tok_flush(t);
+ while ((t = tok_get()) && t->tokno == TOK_WSPACE)
+ tok_flush(t); /* copy white space */
+ if (t) { /* extract path name */
+ path = (t->tokno == '"') ? strsave(t->vstr->str) : in_path;
+ do {
+ tok_flush(t); /* copy until newline */
+ } while (t->tokno != '\n' && (t = tok_get()));
+ }
+ out_line = in_line = line; /* synchronize */
+ out_path = in_path = path; /* synchronize */
+ return;
+
+#ifdef IGNORE_DIRECTIVES
+
+ case TOK_WORD:
+
+ /*
+ * Optionally ignore other #directives. This is only a partial
+ * solution, because the preprocessor will still see them.
+ */
+ {
+ char **cpp;
+ char *cp = t->vstr->str;
+
+ for (cpp = ignore_directives; *cpp; cpp++) {
+ if (STREQUAL(cp, *cpp)) {
+ do {
+ tok_free(t);
+ } while (t->tokno != '\n' && (t = tok_get()));
+ return;
+ }
+ }
+ }
+ /* FALLTHROUGH */
+#endif
+ default:
+ /* Pass through. */
+ put_ch('#');
+ do {
+ tok_flush(t);
+ } while (t->tokno != '\n' && (t = tok_get()));
+ return;
+
+ case 0:
+ /* Hit EOF, punt. */
+ put_ch('#');
+ return;
+ }
+ }
+}
+
+/* backslash_newline - fix up things after reading a backslash-newline pair */
+
+static int backslash_newline()
+{
+ register int c;
+
+ nl_compensate++;
+ return (INPUT(c));
+}
+
+/* tok_get - get next token */
+
+static int last_tokno = '\n';
+
+struct token *tok_get()
+{
+ register struct token *t;
+ register int c;
+ int d;
+
+ /*
+ * Get one from the pool and fill it in. The loop is here in case we hit
+ * a preprocessor control line, which happens in a minority of all cases.
+ * We update the token input path and line info *after* backslash-newline
+ * processing or the newline compensation would go wrong.
+ */
+
+ t = tok_alloc();
+
+ for (;;) {
+ if ((INPUT(c)) == EOF) {
+ tok_free(t);
+ return (0);
+ } else if ((t->line = in_line, t->path = in_path), !isascii(c)) {
+ t->vstr->str[0] = c;
+ t->vstr->str[1] = 0;
+ t->tokno = TOK_OTHER;
+ break;
+ } else if (ISSPACE(c)) {
+ COLLECT(t->vstr, c, ISSPACE(c));
+ t->tokno = TOK_WSPACE;
+ break;
+ } else if (ISALPHA(c)) {
+ COLLECT(t->vstr, c, ISALNUM(c));
+ t->tokno = TOK_WORD;
+ break;
+ } else if (isdigit(c)) {
+ COLLECT(t->vstr, c, isdigit(c));
+ t->tokno = TOK_NUMBER;
+ break;
+ } else if (c == '"' || c == '\'') {
+ t->tokno = read_quoted(t->vstr, c); /* detect missing end quote */
+ break;
+ } else if (ISDOT(c)) {
+ COLLECT(t->vstr, c, ISDOT(c));
+ t->tokno = TOK_OTHER;
+ break;
+ } else if (c == '#' && last_tokno == '\n') {
+ do_control();
+ continue;
+ } else {
+ t->vstr->str[0] = c;
+ if (c == '\n') {
+ in_line++;
+ if (nl_compensate > 0) { /* compensation for bs-nl */
+ UNPUT('\n');
+ nl_compensate--;
+ }
+ } else if (c == '/') {
+ if ((INPUT(d)) == '*') {
+ t->vstr->str[1] = d; /* comment */
+ read_comment(t->vstr);
+ t->tokno = TOK_WSPACE;
+ break;
+ } else {
+ if (d != EOF)
+ UNPUT(d);
+ }
+ } else if (c == '\\') {
+ t->vstr->str[1] = (INPUT(c) == EOF ? 0 : c);
+ t->vstr->str[2] = 0;
+ t->tokno = TOK_OTHER;
+ break;
+ }
+ t->vstr->str[1] = 0;
+ t->tokno = c;
+ break;
+ }
+ }
+ last_tokno = t->tokno;
+ t->end_line = in_line;
+ return (t);
+}
+
+/* read_quoted - read string or character literal, canonicalize escapes */
+
+static int read_quoted(vs, ch)
+register struct vstring *vs;
+int ch;
+{
+ register char *cp = vs->str;
+ register int c;
+ int ret = TOK_OTHER;
+
+ *cp++ = ch;
+
+ /*
+ * Clobber the token type in case of a premature newline or EOF. This
+ * prevents us from attempting to concatenate string constants with
+ * broken ones that have no closing quote.
+ */
+
+ while (INPUT(c) != EOF) {
+ if (c == '\n') { /* newline in string */
+ UNPUT(c);
+ break;
+ }
+ if (VS_ADDCH(vs, cp, c) == 0) /* store character */
+ fatal("out of memory");
+ if (c == ch) { /* closing quote */
+ ret = c;
+ break;
+ }
+ if (c == '\\') { /* parse escape sequence */
+ if ((INPUT(c)) == EOF) { /* EOF, punt */
+ break;
+ } else if (c == 'a') { /* \a -> audible bell */
+ if ((cp = vs_strcpy(vs, cp, BELL)) == 0)
+ fatal("out of memory");
+ } else if (c == 'x') { /* \xhh -> \nnn */
+ cp = read_hex(vs, cp);
+ } else if (ISOCTAL(c) && ch != '\'') {
+ cp = read_octal(vs, cp, c); /* canonicalize \octal */
+ } else {
+ if (VS_ADDCH(vs, cp, c) == 0) /* \other: leave alone */
+ fatal("out of memory");
+ }
+ }
+ }
+ *cp = 0;
+ return (ret);
+}
+
+/* read_comment - stuff a whole comment into one huge token */
+
+static void read_comment(vs)
+register struct vstring *vs;
+{
+ register char *cp = vs->str + 2; /* skip slash star */
+ register int c;
+ register int d;
+
+ while (INPUT(c) != EOF) {
+ if (VS_ADDCH(vs, cp, c) == 0)
+ fatal("out of memory");
+ if (c == '*') {
+ if ((INPUT(d)) == '/') {
+ if (VS_ADDCH(vs, cp, d) == 0)
+ fatal("out of memory");
+ break;
+ } else {
+ if (d != EOF)
+ UNPUT(d);
+ }
+ } else if (c == '\n') {
+ in_line++;
+ } else if (c == '\\') {
+ if ((INPUT(d)) != EOF && VS_ADDCH(vs, cp, d) == 0)
+ fatal("out of memory");
+ }
+ }
+ *cp = 0;
+}
+
+/* read_hex - rewrite hex escape to three-digit octal escape */
+
+static char *read_hex(vs, cp)
+struct vstring *vs;
+register char *cp;
+{
+ register int c;
+ register int i;
+ char buf[BUFSIZ];
+ int len;
+ unsigned val;
+
+ /*
+ * Eat up all subsequent hex digits. Complain later when there are too
+ * many.
+ */
+
+ for (i = 0; i < sizeof(buf) && (INPUT(c) != EOF) && ISHEX(c); i++)
+ buf[i] = c;
+ buf[i] = 0;
+
+ if (i < sizeof(buf) && c)
+ UNPUT(c);
+
+ /*
+ * Convert hex form to three-digit octal form. The three-digit form is
+ * used so that strings can be concatenated without problems. Complain
+ * about malformed input; truncate the result to at most three octal
+ * digits.
+ */
+
+ if (i == 0) {
+ error("\\x escape sequence without hexadecimal digits");
+ if (VS_ADDCH(vs, cp, 'x') == 0)
+ fatal("out of memory");
+ } else {
+ (void) sscanf(buf, "%x", &val);
+ sprintf(buf, "%03o", val);
+ if ((len = strlen(buf)) > 3)
+ error("\\x escape sequence yields non-character value");
+ if ((cp = vs_strcpy(vs, cp, buf + len - 3)) == 0)
+ fatal("out of memory");
+ }
+ return (cp);
+}
+
+/* read_octal - convert octal escape to three-digit format */
+
+static char obuf[] = "00123";
+
+static char *read_octal(vs, cp, c)
+register struct vstring *vs;
+register char *cp;
+register int c;
+{
+ register int i;
+
+#define buf_input (obuf + 2)
+
+ /* Eat up at most three octal digits. */
+
+ buf_input[0] = c;
+ for (i = 1; i < 3 && (INPUT(c) != EOF) && ISOCTAL(c); i++)
+ buf_input[i] = c;
+ buf_input[i] = 0;
+
+ if (i < 3 && c)
+ UNPUT(c);
+
+ /*
+ * Leave three-digit octal escapes alone. Convert one-digit and two-digit
+ * octal escapes to three-digit form by prefixing them with a suitable
+ * number of '0' characters. This is done so that strings can be
+ * concatenated without problems.
+ */
+
+ if ((cp = vs_strcpy(vs, cp, buf_input + i - 3)) == 0)
+ fatal("out of memory");
+ return (cp);
+}
+
+/* put_nl - emit newline and adjust output line count */
+
+void put_nl()
+{
+ put_ch('\n');
+ out_line++;
+}
+
+/* fix_line_control - to adjust path and/or line count info in output */
+
+static void fix_line_control(path, line)
+register char *path;
+register int line;
+{
+
+ /*
+ * This function is called sporadically, so it should not be a problem
+ * that we repeat some of the tests that preceded this function call.
+ *
+ * Emit a newline if we are not at the start of a line.
+ *
+ * If we switch files, or if we jump backwards, emit line control. If we
+ * jump forward, emit the proper number of newlines to compensate.
+ */
+
+ if (last_ch != '\n') /* terminate open line */
+ put_nl();
+ if (path != out_path || line < out_line) { /* file switch or back jump */
+ printf("# %d %s\n", out_line = line, out_path = path);
+ last_ch = '\n';
+ } else { /* forward jump */
+ while (line > out_line)
+ put_nl();
+ }
+}
+
+/* tok_show_ch - output single-character token (not newline) */
+
+void tok_show_ch(t)
+register struct token *t;
+{
+ CHECK_LINE_CONTROL(t->path, t->line);
+
+ put_ch(t->tokno); /* show token contents */
+}
+
+/* tok_show - output (possibly composite) token */
+
+void tok_show(t)
+register struct token *t;
+{
+ register struct token *p;
+
+ if (t->tokno == TOK_LIST) {
+ register struct token *s;
+
+ /*
+ * This branch is completely in terms of tok_xxx() primitives, so
+ * there is no need to check the line control information.
+ */
+
+ for (s = t->head; s; s = s->next) {
+ tok_show_ch(s); /* '(' or ',' or ')' */
+ for (p = s->head; p; p = p->next)
+ tok_show(p); /* show list element */
+ }
+ } else {
+ register char *cp = t->vstr->str;
+
+ /*
+ * Measurements show that it pays off to give special treatment to
+ * single-character tokens. Note that both types of token may cause a
+ * change of output line number.
+ */
+
+ CHECK_LINE_CONTROL(t->path, t->line);
+ if (cp[1] == 0) {
+ put_ch(*cp); /* single-character token */
+ } else {
+ put_str(cp); /* multi_character token */
+ }
+ out_line = t->end_line; /* may span multiple lines */
+ for (p = t->head; p; p = p->next)
+ tok_show(p); /* trailing blanks */
+ }
+}