lxcmntent: coding rules

src/include/lxcmntent.c

 /* Utilities for reading/writing fstab, mtab, etc.
-   Copyright (C) 1995-2000, 2001, 2002, 2003, 2006
-   Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library 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
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with this library; if not, write to the Free Software
-   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (C) 1995-2000, 2001, 2002, 2003, 2006
+ * Free Software Foundation, Inc.
+ * This file is part of the GNU C Library.
+ *
+ * The GNU C Library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * The GNU C Library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  */
 
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE 1
+#endif
 #include <alloca.h>
+#include <macro.h>
+#include <mntent.h>
 #include <stdio.h>
 #include <string.h>
-#include <mntent.h>
 
 /* Since the values in a line are separated by spaces, a name cannot
- contain a space. Therefore some programs encode spaces in names
- by the strings "\040". We undo the encoding when reading an entry.
- The decoding happens in place. */
-static char *
-decode_name (char *buf)
+ * contain a space. Therefore some programs encode spaces in names
+ * by the strings "\040". We undo the encoding when reading an entry.
+ * The decoding happens in place.
+ */
+static char *decode_name(char *buf)
 {
 	char *rp = buf;
 	char *wp = buf;
 
-    do
-    if (rp[0] == '\\' && rp[1] == '0' && rp[2] == '4' && rp[3] == '0')
-    {
+	do {
+		if (rp[0] == '\\' && rp[1] == '0' && rp[2] == '4' &&
+		    rp[3] == '0') {
 			/* \040 is a SPACE. */
 			*wp++ = ' ';
 			rp += 3;
-    }
-    else if (rp[0] == '\\' && rp[1] == '0' && rp[2] == '1' && rp[3] == '1')
-    {
+		} else if (rp[0] == '\\' && rp[1] == '0' && rp[2] == '1' &&
+		           rp[3] == '1') {
 			/* \011 is a TAB. */
 			*wp++ = '\t';
 			rp += 3;
-    }
-    else if (rp[0] == '\\' && rp[1] == '0' && rp[2] == '1' && rp[3] == '2')
-    {
+		} else if (rp[0] == '\\' && rp[1] == '0' && rp[2] == '1' &&
+		           rp[3] == '2') {
 			/* \012 is a NEWLINE. */
 			*wp++ = '\n';
 			rp += 3;
-    }
-    else if (rp[0] == '\\' && rp[1] == '\\')
-    {
+		} else if (rp[0] == '\\' && rp[1] == '\\') {
 			/* We have to escape \\ to be able to represent all characters. */
 			*wp++ = '\\';
 			rp += 1;
-    }
-    else if (rp[0] == '\\' && rp[1] == '1' && rp[2] == '3' && rp[3] == '4')
-    {
+		} else if (rp[0] == '\\' && rp[1] == '1' && rp[2] == '3' &&
+		           rp[3] == '4') {
 			/* \134 is also \\. */
 			*wp++ = '\\';
 			rp += 3;
-    }
-    else
+		} else {
 			*wp++ = *rp;
-    while (*rp++ != '\0');
+		}
+	} while (*rp++ != '\0');
 
 	return buf;
 }
 
 /* Read one mount table entry from STREAM. Returns a pointer to storage
- reused on the next call, or null for EOF or error (use feof/ferror to
- check). */
-struct mntent *getmntent_r (FILE *stream, struct mntent *mp, char *buffer, int bufsiz)
+ * reused on the next call, or null for EOF or error (use feof/ferror to check).
+ */
+struct mntent *getmntent_r(FILE *stream, struct mntent *mp, char *buffer, int bufsiz)
 {
 	char *cp;
 	char *head;
 
-    do
-    {
+	do {
 		char *end_ptr;
 
-        if (fgets (buffer, bufsiz, stream) == NULL)
-        {
+		if (!fgets(buffer, bufsiz, stream))
 			return NULL;
-        }
 
-        end_ptr = strchr (buffer, '\n');
-        if (end_ptr != NULL) /* chop newline */
+		end_ptr = strchr(buffer, '\n');
+		if (end_ptr != NULL) {
+			/* chop newline */
 			*end_ptr = '\0';
-        else
-        {
+		} else {
 			/* Not the whole line was read. Do it now but forget it. */
-            char tmp[1024];
-            while (fgets (tmp, sizeof tmp, stream) != NULL)
-                if (strchr (tmp, '\n') != NULL)
+			char tmp[1024] = {0};
+
+			while (fgets(tmp, sizeof tmp, stream))
+				if (strchr(tmp, '\n') != NULL)
 					break;
 		}
 
-        head = buffer + strspn (buffer, " \t");
+		head = buffer + strspn(buffer, " \t");
 		/* skip empty lines and comment lines: */
-    }
-    while (head[0] == '\0' || head[0] == '#');
+	} while (head[0] == '\0' || head[0] == '#');
 
-    cp = strsep (&head, " \t");
-    mp->mnt_fsname = cp != NULL ? decode_name (cp) : (char *) "";
+	cp = strsep(&head, " \t");
+	mp->mnt_fsname = cp ? decode_name(cp) : (char *)"";
 	if (head)
-        head += strspn (head, " \t");
-    cp = strsep (&head, " \t");
-    mp->mnt_dir = cp != NULL ? decode_name (cp) : (char *) "";
+		head += strspn(head, " \t");
+
+	cp = strsep(&head, " \t");
+	mp->mnt_dir = cp ? decode_name(cp) : (char *)"";
 	if (head)
-        head += strspn (head, " \t");
-    cp = strsep (&head, " \t");
-    mp->mnt_type = cp != NULL ? decode_name (cp) : (char *) "";
+		head += strspn(head, " \t");
+
+	cp = strsep(&head, " \t");
+	mp->mnt_type = cp ? decode_name(cp) : (char *)"";
 	if (head)
-        head += strspn (head, " \t");
-    cp = strsep (&head, " \t");
-    mp->mnt_opts = cp != NULL ? decode_name (cp) : (char *) "";
-    switch (head ? sscanf (head, " %d %d ", &mp->mnt_freq, &mp->mnt_passno) : 0)
-    {
+		head += strspn(head, " \t");
+
+	cp = strsep(&head, " \t");
+	mp->mnt_opts = cp ? decode_name(cp) : (char *)"";
+	if (head) {
+		int ret = sscanf(head, " %d %d ", &mp->mnt_freq, &mp->mnt_passno);
+
+		switch (ret) {
 		case 0:
 			mp->mnt_freq = 0;
 		case 1:
@@ -128,68 +129,74 @@ struct mntent *getmntent_r (FILE *stream, struct mntent *mp, char *buffer, int b
 		case 2:
 			break;
 		}
+	} else {
+		mp->mnt_freq = 0;
+	}
 
 	return mp;
 }
 
-struct mntent *getmntent (FILE *stream)
+struct mntent *getmntent(FILE *stream)
 {
 	static struct mntent m;
 	static char *getmntent_buffer;
 
-    #define BUFFER_SIZE 4096
-    if (getmntent_buffer == NULL) {
-        getmntent_buffer = (char *) malloc (BUFFER_SIZE);
+	if (!getmntent_buffer) {
+		getmntent_buffer = (char *)malloc(LXC_MAX_BUFFER);
+		if (!getmntent_buffer)
+			return NULL;
 	}
 
-    return getmntent_r (stream, &m, getmntent_buffer, BUFFER_SIZE);
-    #undef BUFFER_SIZE
+	return getmntent_r(stream, &m, getmntent_buffer, LXC_MAX_BUFFER);
 }
 
-
 /* Prepare to begin reading and/or writing mount table entries from the
- beginning of FILE. MODE is as for `fopen'. */
-FILE *setmntent (const char *file, const char *mode)
+ * beginning of FILE. MODE is as for `fopen'.
+ */
+FILE *setmntent(const char *file, const char *mode)
 {
 	/* Extend the mode parameter with "c" to disable cancellation in the
-    I/O functions and "e" to set FD_CLOEXEC. */
-    size_t modelen = strlen (mode);
+	 * I/O functions and "e" to set FD_CLOEXEC.
+	 */
+	size_t modelen = strlen(mode);
 	char *newmode;
 
 	newmode = alloca(modelen + 3);
 
-    memcpy (newmode, mode, modelen);
-    memcpy (newmode + modelen, "ce", 3);
-    FILE *result = fopen (file, newmode);
+	memcpy(newmode, mode, modelen);
+	memcpy(newmode + modelen, "ce", 3);
 
-    return result;
+	return fopen (file, newmode);
 }
 
-
 /* Close a stream opened with `setmntent'. */
-int endmntent (FILE *stream)
+int endmntent(FILE *stream)
 {
-    if (stream) /* SunOS 4.x allows for NULL stream */
-    fclose (stream);
-    return 1; /* SunOS 4.x says to always return 1 */
+	/* SunOS 4.x allows for NULL stream */
+	if (stream)
+		fclose(stream);
+
+	/* SunOS 4.x says to always return 1 */
+	return 1;
 }
 
 /* Search MNT->mnt_opts for an option matching OPT.
- Returns the address of the substring, or null if none found. */
-char *hasmntopt (const struct mntent *mnt, const char *opt)
+ * Returns the address of the substring, or null if none found.
+ */
+char *hasmntopt(const struct mntent *mnt, const char *opt)
 {
-    const size_t optlen = strlen (opt);
+	const size_t optlen = strlen(opt);
 	char *rest = mnt->mnt_opts, *p;
 
-    while ((p = strstr (rest, opt)) != NULL)
-    {
-        if ((p == rest || p[-1] == ',')
-            && (p[optlen] == '\0' || p[optlen] == '=' || p[optlen] == ','))
+	while ((p = strstr(rest, opt))) {
+		if ((p == rest || p[-1] == ',') &&
+		    (p[optlen] == '\0' || p[optlen] == '=' || p[optlen] == ','))
 			return p;
 
-        rest = strchr (p, ',');
-        if (rest == NULL)
+		rest = strchr(p, ',');
+		if (!rest)
 			break;
+
 		++rest;
 	}