Initial import

third_party/lex/buf.c

@@ -0,0 +1,286 @@
+/*-*- mode:c;indent-tabs-mode:t;c-basic-offset:8;tab-width:8;coding:utf-8   -*-│
+│vi: set et ft=c ts=8 sw=8 fenc=utf-8                                       :vi│
+└─────────────────────────────────────────────────────────────────────────────*/
+/* clang-format off */
+/* $OpenBSD: buf.c,v 1.7 2015/11/20 18:54:49 tedu Exp $ */
+
+/* flex - tool to generate fast lexical analyzers */
+
+/*  Copyright (c) 1990 The Regents of the University of California. */
+/*  All rights reserved. */
+
+/*  This code is derived from software contributed to Berkeley by */
+/*  Vern Paxson. */
+
+/*  The United States Government has rights in this work pursuant */
+/*  to contract no. DE-AC03-76SF00098 between the United States */
+/*  Department of Energy and the University of California. */
+
+/*  This file is part of flex. */
+
+/*  Redistribution and use in source and binary forms, with or without */
+/*  modification, are permitted provided that the following conditions */
+/*  are met: */
+
+/*  1. Redistributions of source code must retain the above copyright */
+/*     notice, this list of conditions and the following disclaimer. */
+/*  2. Redistributions in binary form must reproduce the above copyright */
+/*     notice, this list of conditions and the following disclaimer in the */
+/*     documentation and/or other materials provided with the distribution. */
+
+/*  Neither the name of the University nor the names of its contributors */
+/*  may be used to endorse or promote products derived from this software */
+/*  without specific prior written permission. */
+
+/*  THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR */
+/*  IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED */
+/*  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR */
+/*  PURPOSE. */
+
+
+#include "libc/str/str.h"
+#include "libc/mem/mem.h"
+#include "libc/fmt/fmt.h"
+#include "libc/math.h"
+#include "libc/conv/conv.h"
+#include "flexdef.h"
+
+/* Take note: The buffer object is sometimes used as a String buffer (one
+ * continuous string), and sometimes used as a list of strings, usually line by
+ * line.
+ *
+ * The type is specified in buf_init by the elt_size. If the elt_size is
+ * sizeof(char), then the buffer should be treated as string buffer. If the
+ * elt_size is sizeof(char*), then the buffer should be treated as a list of
+ * strings.
+ *
+ * Certain functions are only appropriate for one type or the other.
+ */
+
+/* global buffers. */
+struct Buf userdef_buf;		/**< for user #definitions triggered by cmd-line. */
+struct Buf defs_buf;		/**< for #define's autogenerated. List of strings. */
+struct Buf yydmap_buf;		/**< string buffer to hold yydmap elements */
+struct Buf m4defs_buf;		/**< m4 definitions. List of strings. */
+struct Buf top_buf;		/**< contains %top code. String buffer. */
+
+struct Buf *
+buf_print_strings(struct Buf * buf, FILE * out)
+{
+	int i;
+
+	if (!buf || !out)
+		return buf;
+
+	for (i = 0; i < buf->nelts; i++) {
+		const char *s = ((char **) buf->elts)[i];
+		if (s)
+			fprintf(out, "%s", s);
+	}
+	return buf;
+}
+
+/* Append a "%s" formatted string to a string buffer */
+struct Buf *
+buf_prints(struct Buf * buf, const char *fmt, const char *s)
+{
+	char *t;
+	size_t tsz;
+
+	tsz = strlen(fmt) + strlen(s) + 1;
+	t = malloc(tsz);
+	if (!t)
+		flexfatal(_("Allocation of buffer to print string failed"));
+	snprintf(t, tsz, fmt, s);
+	buf = buf_strappend(buf, t);
+	free(t);
+	return buf;
+}
+
+/** Append a line directive to the string buffer.
+ * @param buf A string buffer.
+ * @param filename file name
+ * @param lineno line number
+ * @return buf
+ */
+struct Buf *
+buf_linedir(struct Buf * buf, const char *filename, int lineno)
+{
+	const char *src;
+	char *dst, *t;
+	size_t tsz;
+
+	tsz = strlen("#line \"\"\n") +	/* constant parts */
+	    2 * strlen(filename) +	/* filename with possibly all backslashes escaped */
+	    (int) (1 + log10(abs(lineno))) +	/* line number */
+	    1;			/* NUL */
+	t = malloc(tsz);
+	if (!t)
+		flexfatal(_("Allocation of buffer for line directive failed"));
+	dst = t + snprintf(t, tsz, "#line %d \"", lineno);
+	for (src = filename; *src; *dst++ = *src++)
+		if (*src == '\\')	/* escape backslashes */
+			*dst++ = '\\';
+	*dst++ = '"';
+	*dst++ = '\n';
+	*dst = '\0';
+	buf = buf_strappend(buf, t);
+	free(t);
+	return buf;
+}
+
+
+/** Append the contents of @a src to @a dest.
+ * @param @a dest the destination buffer
+ * @param @a dest the source buffer
+ * @return @a dest
+ */
+struct Buf *
+buf_concat(struct Buf * dest, const struct Buf * src)
+{
+	buf_append(dest, src->elts, src->nelts);
+	return dest;
+}
+
+
+/* Appends n characters in str to buf. */
+struct Buf *
+buf_strnappend(struct Buf *buf, const char *str, int n)
+{
+	buf_append(buf, str, n + 1);
+
+	/* "undo" the '\0' character that buf_append() already copied. */
+	buf->nelts--;
+
+	return buf;
+}
+
+/* Appends characters in str to buf. */
+struct Buf *
+buf_strappend(struct Buf *buf, const char *str)
+{
+	return buf_strnappend(buf, str, strlen(str));
+}
+
+/* appends "#define str def\n" */
+struct Buf *
+buf_strdefine(struct Buf *buf, const char *str, const char *def2)
+{
+	buf_strappend(buf, "#define ");
+	buf_strappend(buf, " ");
+	buf_strappend(buf, str);
+	buf_strappend(buf, " ");
+	buf_strappend(buf, def2);
+	buf_strappend(buf, "\n");
+	return buf;
+}
+
+/** Pushes "m4_define( [[def]], [[val]])m4_dnl" to end of buffer.
+ * @param buf A buffer as a list of strings.
+ * @param def The m4 symbol to define.
+ * @param val The definition; may be NULL.
+ * @return buf
+ */
+struct Buf *
+buf_m4_define(struct Buf * buf, const char *def2, const char *val)
+{
+	const char *fmt = "m4_define( [[%s]], [[%s]])m4_dnl\n";
+	char *str;
+	size_t strsz;
+
+	val = val ? val : "";
+	strsz = strlen(fmt) + strlen(def2) + strlen(val) + 2;
+	str = malloc(strsz);
+	if (!str)
+		flexfatal(_("Allocation of buffer for m4 def failed"));
+
+	snprintf(str, strsz, fmt, def2, val);
+	buf_append(buf, &str, 1);
+	return buf;
+}
+
+/** Pushes "m4_undefine([[def]])m4_dnl" to end of buffer.
+ * @param buf A buffer as a list of strings.
+ * @param def The m4 symbol to undefine.
+ * @return buf
+ */
+struct Buf *
+buf_m4_undefine(struct Buf * buf, const char *def2)
+{
+	const char *fmt = "m4_undefine( [[%s]])m4_dnl\n";
+	char *str;
+	size_t strsz;
+
+	strsz = strlen(fmt) + strlen(def2) + 2;
+	str = malloc(strsz);
+	if (!str)
+		flexfatal(_("Allocation of buffer for m4 undef failed"));
+
+	snprintf(str, strsz, fmt, def2);
+	buf_append(buf, &str, 1);
+	return buf;
+}
+
+/* create buf with 0 elements, each of size elem_size. */
+void
+buf_init(struct Buf *buf, size_t elem_size)
+{
+	buf->elts = NULL;
+	buf->nelts = 0;
+	buf->elt_size = elem_size;
+	buf->nmax = 0;
+}
+
+/* frees memory */
+void
+buf_destroy(struct Buf *buf)
+{
+	free(buf->elts);
+	buf->elts = NULL;
+}
+
+
+/* appends ptr[] to buf, grow if necessary.
+ * n_elem is number of elements in ptr[], NOT bytes.
+ * returns buf.
+ * We grow by mod(512) boundaries.
+ */
+
+struct Buf *
+buf_append(struct Buf *buf, const void *ptr, int n_elem)
+{
+	int n_alloc = 0;
+
+	if (!ptr || n_elem == 0)
+		return buf;
+
+	/* May need to alloc more. */
+	if (n_elem + buf->nelts > buf->nmax) {
+
+		/* exact amount needed... */
+		n_alloc = (n_elem + buf->nelts) * buf->elt_size;
+
+		/* ...plus some extra */
+		if (((n_alloc * buf->elt_size) % 512) != 0
+		    && buf->elt_size < 512)
+			n_alloc +=
+			    (512 -
+			    ((n_alloc * buf->elt_size) % 512)) /
+			    buf->elt_size;
+
+		if (!buf->elts)
+			buf->elts =
+			    allocate_array(n_alloc, buf->elt_size);
+		else
+			buf->elts =
+			    reallocate_array(buf->elts, n_alloc,
+			    buf->elt_size);
+
+		buf->nmax = n_alloc;
+	}
+	memcpy((char *) buf->elts + buf->nelts * buf->elt_size, ptr,
+	    n_elem * buf->elt_size);
+	buf->nelts += n_elem;
+
+	return buf;
+}