1 files changed, 394 insertions, 0 deletions
diff --git a/old-extension/fileop.c b/old-extension/fileop.c
new file mode 100644
index 00000000..86f62576
--- /dev/null
+++ b/old-extension/fileop.c
@@ -0,0 +1,394 @@
+/*
+ * fileop.c -- Builtin functions for binary I/O and other interfaces to
+ *	the filesystem.
+ */
+
+/*
+ * Copyright (C) 2012 the Free Software Foundation, Inc.
+ * 
+ * This file is part of GAWK, the GNU implementation of the
+ * AWK Programming Language.
+ * 
+ * GAWK is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * GAWK is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
+ */
+
+#include "awk.h"
+
+int plugin_is_GPL_compatible;
+
+typedef struct file_struct {
+	struct file_struct *next;
+	FILE *fp;
+	int flags;
+	char path[1];
+} file_t;
+
+static file_t *files;
+static file_t *file_open(const char *builtin_name, int nargs, int do_open);
+static int mode2flags(const char *mode);
+
+/* do_fread --- read from file */
+
+static NODE *
+do_fread(int nargs)
+{
+	NODE *arg;
+	size_t rlen, count;
+	file_t *f;
+	char *rbuf;
+
+	f = file_open("fread", nargs, true);
+
+	arg = get_scalar_argument(2, false);
+	force_number(arg);
+	rlen = get_number_ui(arg);
+
+	emalloc(rbuf, char *, rlen + 2, "do_fread");
+	if ((count = fread(rbuf, 1, rlen, f->fp)) < rlen) {
+		if (! feof(f->fp))
+			update_ERRNO_int(errno);
+	}
+	return make_str_node(rbuf, count, ALREADY_MALLOCED);
+}
+
+/* do_fwrite --- write to file */
+
+static NODE *
+do_fwrite(int nargs)
+{
+	NODE *arg;
+	file_t *f;
+	size_t count = 0;
+
+	f = file_open("fwrite", nargs, true);
+
+	arg = get_scalar_argument(2, false);
+	force_string(arg);
+	if (arg->stlen > 0) {
+		count = fwrite(arg->stptr, 1, arg->stlen, f->fp);
+		if (count < arg->stlen)
+			update_ERRNO_int(errno);
+	}
+	return make_number(count);
+}
+
+/* do_fseek --- set the file position indicator */
+
+static NODE *
+do_fseek(int nargs)
+{
+	NODE *arg;
+	long offset;
+	file_t *f;
+	int whence = 0, ret = 0;
+
+	f = file_open("fseek", nargs, true);
+
+	arg = get_scalar_argument(2, false);
+	force_number(arg);
+	offset = get_number_si(arg);
+
+	arg = get_scalar_argument(3, false);
+	force_string(arg);
+	if (strcasecmp(arg->stptr, "SEEK_SET") == 0)
+		whence = SEEK_SET;
+	else if (strcasecmp(arg->stptr, "SEEK_CUR") == 0)
+		whence = SEEK_CUR;
+	else if (strcasecmp(arg->stptr, "SEEK_END") == 0)
+		whence = SEEK_END;
+	else
+		fatal(_("fseek: `%.*s' is not a valid 4th argument"),
+			(int) arg->stlen, arg->stptr);
+
+	if (fseek(f->fp, offset, whence) < 0) {
+		update_ERRNO_int(errno);
+		ret = -1;
+	}
+	return make_number(ret);
+}
+
+/* do_ftruncate --- truncate the file to a specified length */
+
+static NODE *
+do_ftruncate(int nargs)
+{
+	NODE *arg;
+	file_t *f;
+	off_t len;
+	int ret = 0;
+
+	f = file_open("ftruncate", nargs, true);
+	arg = get_scalar_argument(2, false);
+	force_number(arg);
+	len = (off_t) get_number_si(arg);
+	if (ftruncate(fileno(f->fp), len) < 0) {
+		update_ERRNO_int(errno);
+		ret = -1;
+	}
+	return make_number(ret);
+}
+
+/* do_unlink --- delete the name from the filesystem */
+
+static NODE *
+do_unlink(int nargs)
+{
+	NODE *file;
+	int ret = 0;
+
+	file = get_scalar_argument(0, false);
+	force_string(file);
+	if (file->stlen == 0)
+		fatal(_("unlink: filename has empty string value"));
+	if (unlink(file->stptr) < 0) {
+		update_ERRNO_int(errno);
+		ret = -1;
+	}
+	return make_number(ret);
+}
+
+/* do_flush --- flush buffered data to file */
+
+static NODE *
+do_flush(int nargs)
+{
+	file_t *f;
+	int status = -1;
+
+	f = file_open("flush", nargs, false);
+	if (f != NULL) {
+		status = fflush(f->fp);
+		if (status != 0)
+			update_ERRNO_int(errno);
+	}
+	return make_number(status);
+}
+
+/* do_fclose --- close an open file */
+
+static NODE *
+do_fclose(int nargs)
+{
+	file_t *f;
+	int status = -1;
+
+	f = file_open("fclose", nargs, false);
+	if (f != NULL) {
+		status = fclose(f->fp);
+		if (status != 0)
+			update_ERRNO_int(errno);
+		assert(files == f);
+		files = f->next;
+		efree(f);
+	}
+	return make_number(status);
+}
+
+/* do_filesize --- return the size of the file */
+
+static NODE *
+do_filesize(int nargs)
+{
+	NODE *file;
+	struct stat sbuf;
+	AWKNUM d = -1.0;
+
+	file = get_scalar_argument(0, false);
+	force_string(file);
+	if (file->stlen == 0)
+		fatal(_("filesize: filename has empty string value"));
+
+	if (stat(file->stptr, & sbuf) < 0) {
+		update_ERRNO_int(errno);
+		goto ferror;
+	}
+	if ((sbuf.st_mode & S_IFMT) != S_IFREG) {
+		errno = EINVAL;
+		update_ERRNO_int(errno);
+		goto ferror;
+	}
+	d = sbuf.st_size;
+
+ferror:
+	return make_number(d);
+}
+
+/* do_file_exists --- check if path exists in the filesystem */
+
+static NODE *
+do_file_exists(int nargs)
+{
+	NODE *file;
+	struct stat sbuf;
+	int ret = 1;
+
+	file = get_scalar_argument(0, false);
+	force_string(file);
+	if (file->stlen == 0)
+		fatal(_("file_exists: filename has empty string value"));
+
+	if (stat(file->stptr, & sbuf) < 0) {
+		if (errno != ENOENT)
+			update_ERRNO_int(errno);
+		ret = 0;
+	}
+	return make_number(ret);
+}
+
+
+/* file_open --- open a file or find an already opened file */
+
+static file_t *
+file_open(const char *builtin_name, int nargs, int do_open)
+{
+	NODE *file, *mode;
+	file_t *f, *prev;
+	FILE *fp;
+	int flags;
+	char *path;
+
+	if (nargs < 2)
+		cant_happen();
+
+	file = get_scalar_argument(0, false);
+	force_string(file);
+	mode = get_scalar_argument(1, true);
+	force_string(mode);
+
+	if (file->stlen == 0)
+		fatal(_("%s: filename has empty string value"), builtin_name);
+	if (mode->stlen == 0)
+		fatal(_("%s: mode has empty string value"), builtin_name);
+
+	flags = mode2flags(mode->stptr);
+	if (flags < 0)
+		fatal(_("%s: invalid mode `%.*s'"), builtin_name,
+			(int) mode->stlen, mode->stptr);
+
+	path = file->stptr;
+	for (prev = NULL, f = files; f != NULL; prev = f, f = f->next) {
+		if (strcmp(f->path, path) == 0 && f->flags == flags) {
+			/* Move to the head of the list */
+			if (prev != NULL) {
+				prev->next = f->next;
+				f->next = files;
+				files = f;
+			}
+			return f;
+		}
+	}
+
+	if (! do_open) {
+		if (do_lint)
+			lintwarn(_("%s: `%.*s' is not an open file"),
+				builtin_name, (int) file->stlen, file->stptr);
+		return NULL;
+	}
+
+	fp = fopen(path, mode->stptr);
+	if (fp == NULL)
+		fatal(_("%s: cannot open file `%.*s'"),
+			builtin_name, (int) file->stlen, file->stptr);
+
+	os_close_on_exec(fileno(fp), path, "", "");
+
+	emalloc(f, file_t *, sizeof(file_t) + file->stlen + 1, "file_open");
+	memcpy(f->path, path, file->stlen + 1);
+	f->fp = fp;
+	f->flags = flags;
+	f->next = files;
+	files = f;
+	return f;
+}
+
+
+/*
+ * mode2flags --- convert a string mode to an integer flag;
+ *	modified from str2mode in io.c.
+ */
+
+static int
+mode2flags(const char *mode)
+{
+	int ret = -1;
+	const char *second;
+
+	if (mode == NULL || mode[0] == '\0')
+		return -1;
+
+	second = & mode[1];
+
+	if (*second == 'b')
+		second++;
+
+	switch(mode[0]) {
+	case 'r':
+		ret = O_RDONLY;
+		if (*second == '+' || *second == 'w')
+			ret = O_RDWR;
+		break;
+
+	case 'w':
+		ret = O_WRONLY|O_CREAT|O_TRUNC;
+		if (*second == '+' || *second == 'r')
+			ret = O_RDWR|O_CREAT|O_TRUNC;
+		break;
+
+	case 'a':
+		ret = O_WRONLY|O_APPEND|O_CREAT;
+		if (*second == '+')
+			ret = O_RDWR|O_APPEND|O_CREAT;
+		break;
+
+	default:
+		ret = -1;
+	}
+	if (ret != -1 && strchr(mode, 'b') != NULL)
+		ret |= O_BINARY;
+	return ret;
+}
+
+
+/* dlload --- load new builtins in this library */
+
+NODE *
+dlload(NODE *tree, void *dl)
+{
+	make_old_builtin("fseek", do_fseek, 4);
+	make_old_builtin("fread", do_fread, 3);
+	make_old_builtin("fwrite", do_fwrite, 3);
+	make_old_builtin("flush", do_flush, 2);
+	make_old_builtin("filesize", do_filesize, 1);
+	make_old_builtin("file_exists", do_file_exists, 1);
+	make_old_builtin("fclose", do_fclose, 2);
+	make_old_builtin("ftruncate", do_ftruncate, 3);
+	make_old_builtin("unlink", do_unlink, 1);
+	return make_number((AWKNUM) 0);
+}
+
+
+/* dlunload --- routine called when exiting */ 
+
+void
+dlunload()
+{
+	file_t *f;
+	for (f = files; f != NULL; f = f->next) {
+		if (f->fp != NULL) {
+			fclose(f->fp);
+			f->fp = NULL;
+		}
+	}
+}