From 31d6734457b9cafeeaa862750c2afa80aa67816c Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sat, 3 Jan 2015 15:15:47 +0100 Subject: libpwdgrp: tweak comments, replace one xmalloc with xzalloc Signed-off-by: Denys Vlasenko --- libpwdgrp/pwd_grp.c | 40 +++++++++++++++++----------------------- 1 file changed, 17 insertions(+), 23 deletions(-) (limited to 'libpwdgrp/pwd_grp.c') diff --git a/libpwdgrp/pwd_grp.c b/libpwdgrp/pwd_grp.c index 0d8e2bb5c..823884edc 100644 --- a/libpwdgrp/pwd_grp.c +++ b/libpwdgrp/pwd_grp.c @@ -1,5 +1,5 @@ /* vi: set sw=4 ts=4: */ -/* Copyright (C) 2014 Tito Ragusa +/* Copyright (C) 2014 Tito Ragusa * * Licensed under GPLv2 or later, see file LICENSE in this source tree. */ @@ -9,38 +9,33 @@ * Rewrite of some parts. Main differences are: * * 1) the buffer for getpwuid, getgrgid, getpwnam, getgrnam is dynamically - * allocated and reused by later calls. if ERANGE error pops up it is - * reallocated to the size of the longest line found so far in the - * passwd/group files and reused for later calls. + * allocated and reused by later calls. * If ENABLE_FEATURE_CLEAN_UP is set the buffers are freed at program * exit using the atexit function to make valgrind happy. * 2) the passwd/group files: * a) must contain the expected number of fields (as per count of field * delimeters ":") or we will complain with a error message. - * b) leading or trailing whitespace in fields is allowed and handled. + * b) leading or trailing whitespace in fields is stripped. * c) some fields are not allowed to be empty (e.g. username, uid/gid, * homedir, shell) and in this case NULL is returned and errno is * set to EINVAL. This behaviour could be easily changed by * modifying PW_DEF, GR_DEF, SP_DEF strings (uppercase * makes a field mandatory). * d) the string representing uid/gid must be convertible by strtoXX - * functions or NULL is returned and errno is set to EINVAL. - * e) leading or trailing whitespaces in member names and empty members - * are allowed and handled. - * 3) the internal function for getgrouplist uses a dynamically allocated - * buffer and retries with a bigger one in case it is too small; - * 4) the _r functions use the user supplied buffers that are never reallocated - * but use mostly the same common code as the other functions. - * 5) at the moment only the functions really used by busybox code are + * functions, or errno is set to EINVAL. + * e) leading or trailing whitespace in group member names are stripped. + * 3) the internal function for getgrouplist uses dynamically allocated buffer. + * 4) at the moment only the functions really used by busybox code are * implemented, if you need a particular missing function it should be * easy to write it by using the internal common code. */ #include "libbb.h" -/* S = string not empty, s = string maybe empty, */ -/* I = uid,gid, l = long maybe empty, m = members,*/ -/* r = reserved */ +/* S = string not empty, s = string maybe empty, + * I = uid,gid, l = long maybe empty, m = members, + * r = reserved + */ #define PW_DEF "SsIIsSS" #define GR_DEF "SsIm" #define SP_DEF "Ssllllllr" @@ -99,7 +94,8 @@ static const struct const_passdb const_sp_db = { _PATH_SHADOW, sp_off, SP_DEF, s /* We avoid having big global data. */ struct statics { - /* It's ok to use one buffer for getpwuid and getpwnam. Manpage says: + /* It's ok to use same buffer (db[0].malloced) for getpwuid and getpwnam. + * Manpage says: * "The return value may point to a static area, and may be overwritten * by subsequent calls to getpwent(), getpwnam(), or getpwuid()." */ @@ -124,14 +120,12 @@ static struct statics *get_S(void) return ptr_to_statics; } -/**********************************************************************/ -/* Internal functions */ -/**********************************************************************/ +/* Internal functions */ /* Divide the passwd/group/shadow record in fields * by substituting the given delimeter * e.g. ':' or ',' with '\0'. - * Returns the number of fields found. + * Returns the number of fields found. * Strips leading and trailing whitespace in fields. */ static int tokenize(char *buffer, int ch) @@ -328,7 +322,7 @@ int FAST_FUNC getpwnam_r(const char *name, struct passwd *struct_buf, char *buff } #if ENABLE_USE_BB_SHADOW int FAST_FUNC getspnam_r(const char *name, struct spwd *struct_buf, char *buffer, size_t buflen, - struct spwd **result) + struct spwd **result) { *result = struct_buf; return getXXnam_r(name, (2 << 2) + 0, buffer, buflen, result); @@ -461,7 +455,7 @@ static gid_t* FAST_FUNC getgrouplist_internal(int *ngroups_ptr, get_S(); /* We alloc space for 8 gids at a time. */ - group_list = xmalloc(8 * sizeof(group_list[0])); + group_list = xzalloc(8 * sizeof(group_list[0])); group_list[0] = gid; ngroups = 1; -- cgit v1.2.3