util.h

samba最新软件

/* 
   Unix SMB/CIFS implementation.
   Utility functions for Samba
   Copyright (C) Andrew Tridgell 1992-1999
   Copyright (C) Jelmer Vernooij 2005
    
   This program 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.
   
   This program 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, see <http://www.gnu.org/licenses/>.
*/

#ifndef _SAMBA_UTIL_H_
#define _SAMBA_UTIL_H_

#include "util/attr.h"

#include "charset/charset.h"

/* for TALLOC_CTX */
#include <talloc.h>

/**
 * @file
 * @brief Helpful macros
 */

struct smbsrv_tcon;

extern const char *logfile;
extern const char *panic_action;

#include "util/time.h"
#include "util/data_blob.h"
#include "util/xfile.h"
#include "util/debug.h"
#include "util/mutex.h"
#include "util/byteorder.h"

/**
  this is a warning hack. The idea is to use this everywhere that we
  get the "discarding const" warning from gcc. That doesn't actually
  fix the problem of course, but it means that when we do get to
  cleaning them up we can do it by searching the code for
  discard_const.

  It also means that other error types aren't as swamped by the noise
  of hundreds of const warnings, so we are more likely to notice when
  we get new errors.

  Please only add more uses of this macro when you find it
  _really_ hard to fix const warnings. Our aim is to eventually use
  this function in only a very few places.

  Also, please call this via the discard_const_p() macro interface, as that
  makes the return type safe.
*/
#ifndef discard_const
#define discard_const(ptr) ((void *)((uintptr_t)(ptr)))
#endif

/** Type-safe version of discard_const */
#ifndef discard_const_p
#define discard_const_p(type, ptr) ((type *)discard_const(ptr))
#endif

/**
 * assert macros 
 */
#define SMB_ASSERT(b) do { if (!(b)) { \
	DEBUG(0,("PANIC: assert failed at %s(%d)\n", __FILE__, __LINE__)); \
	smb_panic("assert failed"); }} while (0)

#ifndef SAFE_FREE /* Oh no this is also defined in tdb.h */
/**
 * Free memory if the pointer and zero the pointer.
 *
 * @note You are explicitly allowed to pass NULL pointers -- they will
 * always be ignored.
 **/
#define SAFE_FREE(x) do { if ((x) != NULL) {free(discard_const_p(void *, (x))); (x)=NULL;} } while(0)
#endif

/** 
 * Type-safe version of malloc. Allocated one copy of the 
 * specified data type.
 */
#define malloc_p(type) (type *)malloc(sizeof(type))

/**
 * Allocate an array of elements of one data type. Does type-checking.
 */
#define malloc_array_p(type, count) (type *)realloc_array(NULL, sizeof(type), count)

/** 
 * Resize an array of elements of one data type. Does type-checking.
 */
#define realloc_p(p, type, count) (type *)realloc_array(p, sizeof(type), count)

#if defined(VALGRIND)
#define strlen(x) valgrind_strlen(x)
#endif

/** 
 * zero a structure 
 */
#ifndef ZERO_STRUCT
#define ZERO_STRUCT(x) memset((char *)&(x), 0, sizeof(x))
#endif

/** 
 * zero a structure given a pointer to the structure 
 */
#ifndef ZERO_STRUCTP
#define ZERO_STRUCTP(x) do { if ((x) != NULL) memset((char *)(x), 0, sizeof(*(x))); } while(0)
#endif

/** 
 * zero a structure given a pointer to the structure - no zero check 
 */
#ifndef ZERO_STRUCTPN
#define ZERO_STRUCTPN(x) memset((char *)(x), 0, sizeof(*(x)))
#endif

/* zero an array - note that sizeof(array) must work - ie. it must not be a
   pointer */
#ifndef ZERO_ARRAY
#define ZERO_ARRAY(x) memset((char *)(x), 0, sizeof(x))
#endif

/**
 * work out how many elements there are in a static array 
 */
#ifndef ARRAY_SIZE
#define ARRAY_SIZE(a) (sizeof(a)/sizeof(a[0]))
#endif

/** 
 * pointer difference macro 
 */
#ifndef PTR_DIFF
#define PTR_DIFF(p1,p2) ((ptrdiff_t)(((const char *)(p1)) - (const char *)(p2)))
#endif

/* The following definitions come from lib/util/fault.c  */


/**
 * Write backtrace to debug log
 */
_PUBLIC_ void call_backtrace(void);

/**
 Something really nasty happened - panic !
**/
_PUBLIC_ _NORETURN_ void smb_panic(const char *why);

/**
setup our fault handlers
**/
_PUBLIC_ void fault_setup(const char *pname);

/**
  register a fault handler. 
  Should only be called once in the execution of smbd.
*/
_PUBLIC_ bool register_fault_handler(const char *name, void (*fault_handler)(int sig));

/* The following definitions come from lib/util/signal.c  */


/**
 Block sigs.
**/
void BlockSignals(bool block, int signum);

/**
 Catch a signal. This should implement the following semantics:

 1) The handler remains installed after being called.
 2) The signal should be blocked during handler execution.
**/
void (*CatchSignal(int signum,void (*handler)(int )))(int);

/**
 Ignore SIGCLD via whatever means is necessary for this OS.
**/
void CatchChild(void);

/**
 Catch SIGCLD but leave the child around so it's status can be reaped.
**/
void CatchChildLeaveStatus(void);

/* The following definitions come from lib/util/system.c  */


struct in_addr;

/**************************************************************************
A wrapper for gethostbyname() that tries avoids looking up hostnames 
in the root domain, which can cause dial-on-demand links to come up for no
apparent reason.
****************************************************************************/
_PUBLIC_ struct hostent *sys_gethostbyname(const char *name);
_PUBLIC_ struct in_addr sys_inet_makeaddr(int net, int host);

/* The following definitions come from lib/util/genrand.c  */

/**
 Copy any user given reseed data.
**/
_PUBLIC_ void set_rand_reseed_callback(void (*fn)(void *, int *), void *);

/**
 * Tell the random number generator it needs to reseed.
 */
_PUBLIC_ void set_need_random_reseed(void);

/**
 Interface to the (hopefully) good crypto random number generator.
 Will use our internal PRNG if more than 40 bytes of random generation
 has been requested, otherwise tries to read from /dev/random
**/
_PUBLIC_ void generate_random_buffer(uint8_t *out, int len);

/**
 Interface to the (hopefully) good crypto random number generator.
 Will always use /dev/urandom if available.
**/
_PUBLIC_ void generate_secret_buffer(uint8_t *out, int len);

/**
  generate a single random uint32_t
**/
_PUBLIC_ uint32_t generate_random(void);

/**
  very basic password quality checker
**/
_PUBLIC_ bool check_password_quality(const char *s);

/**
 Use the random number generator to generate a random string.
**/
_PUBLIC_ char *generate_random_str_list(TALLOC_CTX *mem_ctx, size_t len, const char *list);

/**
 * Generate a random text string consisting of the specified length.
 * The returned string will be allocated.
 *
 * Characters used are: ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+_-#.,
 */
_PUBLIC_ char *generate_random_str(TALLOC_CTX *mem_ctx, size_t len);

/* The following definitions come from lib/util/dprintf.c  */

_PUBLIC_ void d_set_iconv(smb_iconv_t);
_PUBLIC_ int d_vfprintf(FILE *f, const char *format, va_list ap) PRINTF_ATTRIBUTE(2,0);
_PUBLIC_ int d_fprintf(FILE *f, const char *format, ...) PRINTF_ATTRIBUTE(2,3);
_PUBLIC_ int d_printf(const char *format, ...) PRINTF_ATTRIBUTE(1,2);
_PUBLIC_ void display_set_stderr(void);

/* The following definitions come from lib/util/util_str.c  */


/**
 Trim the specified elements off the front and back of a string.
**/
_PUBLIC_ bool trim_string(char *s, const char *front, const char *back);

/**
 Find the number of 'c' chars in a string
**/
_PUBLIC_ _PURE_ size_t count_chars(const char *s, char c);

/**
 Safe string copy into a known length string. maxlength does not
 include the terminating zero.
**/
_PUBLIC_ char *safe_strcpy(char *dest,const char *src, size_t maxlength);

/**
 Safe string cat into a string. maxlength does not
 include the terminating zero.
**/
_PUBLIC_ char *safe_strcat(char *dest, const char *src, size_t maxlength);

/**
 Routine to get hex characters and turn them into a 16 byte array.
 the array can be variable length, and any non-hex-numeric
 characters are skipped.  "0xnn" or "0Xnn" is specially catered
 for.

 valid examples: "0A5D15"; "0x15, 0x49, 0xa2"; "59\ta9\te3\n"


**/
_PUBLIC_ size_t strhex_to_str(char *p, size_t len, const char *strhex);

/** 
 * Parse a hex string and return a data blob. 
 */
_PUBLIC_ _PURE_ DATA_BLOB strhex_to_data_blob(const char *strhex) ;

/**
 * Routine to print a buffer as HEX digits, into an allocated string.
 */
_PUBLIC_ void hex_encode(const unsigned char *buff_in, size_t len, char **out_hex_buffer);

/**
 * talloc version of hex_encode()
 */
_PUBLIC_ char *hex_encode_talloc(TALLOC_CTX *mem_ctx, const unsigned char *buff_in, size_t len);

/**
 Substitute a string for a pattern in another string. Make sure there is 
 enough room!

 This routine looks for pattern in s and replaces it with 
 insert. It may do multiple replacements.

 Any of " ; ' $ or ` in the insert string are replaced with _
 if len==0 then the string cannot be extended. This is different from the old
 use of len==0 which was for no length checks to be done.
**/
_PUBLIC_ void string_sub(char *s,const char *pattern, const char *insert, size_t len);


_PUBLIC_ char *string_sub_talloc(TALLOC_CTX *mem_ctx, const char *s, 
				const char *pattern, const char *insert);

/**
 Similar to string_sub() but allows for any character to be substituted. 
 Use with caution!
 if len==0 then the string cannot be extended. This is different from the old
 use of len==0 which was for no length checks to be done.
**/
_PUBLIC_ void all_string_sub(char *s,const char *pattern,const char *insert, size_t len);

/**
 Unescape a URL encoded string, in place.
**/
_PUBLIC_ void rfc1738_unescape(char *buf);
size_t valgrind_strlen(const char *s);

/**
  format a string into length-prefixed dotted domain format, as used in NBT
  and in some ADS structures
**/
_PUBLIC_ const char *str_format_nbt_domain(TALLOC_CTX *mem_ctx, const char *s);

/**
 * Add a string to an array of strings.
 *
 * num should be a pointer to an integer that holds the current 
 * number of elements in strings. It will be updated by this function.
 */
_PUBLIC_ bool add_string_to_array(TALLOC_CTX *mem_ctx,
			 const char *str, const char ***strings, int *num);

/**
  varient of strcmp() that handles NULL ptrs
**/
_PUBLIC_ int strcmp_safe(const char *s1, const char *s2);

/**
return the number of bytes occupied by a buffer in ASCII format
the result includes the null termination
limited by 'n' bytes
**/
_PUBLIC_ size_t ascii_len_n(const char *src, size_t n);

/**
 Return a string representing a CIFS attribute for a file.
**/
_PUBLIC_ char *attrib_string(TALLOC_CTX *mem_ctx, uint32_t attrib);

/**
 Set a boolean variable from the text value stored in the passed string.
 Returns true in success, false if the passed string does not correctly 
 represent a boolean.
**/
_PUBLIC_ bool set_boolean(const char *boolean_string, bool *boolean);

/**
 * Parse a string containing a boolean value.
 *
 * val will be set to the read value.
 *
 * @retval true if a boolean value was parsed, false otherwise.
 */
_PUBLIC_ bool conv_str_bool(const char * str, bool * val);

/**
 * Convert a size specification like 16K into an integral number of bytes. 
 **/
_PUBLIC_ bool conv_str_size(const char * str, uint64_t * val);