lib/util: add pre and post panic action hooks

[ctdb.git] / lib / util / util.h

/* 
   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_

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

struct smbsrv_tcon;

#ifdef _SAMBA_BUILD_
extern const char *logfile;
#endif
extern const char *panic_action;
extern void (*pre_panic_action_hook)(void);
extern void (*post_panic_action_hook)(void);

/**
 * assert macros 
 */
#ifdef DEVELOPER
#define SMB_ASSERT(b) do { if (!(b)) { \
        DEBUG(0,("PANIC: assert failed at %s(%d): %s\n", \
                 __FILE__, __LINE__, #b)); smb_panic("assert failed: " #b); }} while(0)
#else
/* redefine the assert macro for non-developer builds */
#define SMB_ASSERT(b) do { if (!(b)) { \
        DEBUG(0,("PANIC: assert failed at %s(%d): %s\n", \
            __FILE__, __LINE__, #b)); }} while (0)
#endif

#if _SAMBA_BUILD_ == 4
#ifdef VALGRIND
#define strlen(x) valgrind_strlen(x)
size_t valgrind_strlen(const char *s);
#endif
#endif

#ifndef ABS
#define ABS(a) ((a)>0?(a):(-(a)))
#endif

/**
 * 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/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 p_len, const char *strhex, size_t strhex_len);

#ifdef _SAMBA_BUILD_
/** 
 * Parse a hex string and return a data blob. 
 */
_PUBLIC_ _PURE_ DATA_BLOB strhex_to_data_blob(TALLOC_CTX *mem_ctx, const char *strhex) ;
#endif

/**
 * 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);

/**
  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);

/**
 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);

#if _SAMBA_BUILD_ == 4
/**
 * Convert a size specification like 16K into an integral number of bytes. 
 **/
_PUBLIC_ bool conv_str_size(const char * str, uint64_t * val);
#endif

/**
 * Parse a uint64_t value from a string
 *
 * val will be set to the value read.
 *
 * @retval true if parsing was successful, false otherwise
 */
_PUBLIC_ bool conv_str_u64(const char * str, uint64_t * val);

/**
return the number of bytes occupied by a buffer in CH_UTF16 format
the result includes the null termination
**/
_PUBLIC_ size_t utf16_len(const void *buf);

/**
return the number of bytes occupied by a buffer in CH_UTF16 format
the result includes the null termination
limited by 'n' bytes
**/
_PUBLIC_ size_t utf16_len_n(const void *src, size_t n);
_PUBLIC_ size_t ucs2_align(const void *base_ptr, const void *p, int flags);

/**
Do a case-insensitive, whitespace-ignoring string compare.
**/
_PUBLIC_ int strwicmp(const char *psz1, const char *psz2);

/**
 String replace.
**/
_PUBLIC_ void string_replace(char *s, char oldc, char newc);

/**
 * Compare 2 strings.
 *
 * @note The comparison is case-insensitive.
 **/
_PUBLIC_ bool strequal(const char *s1, const char *s2);

/* The following definitions come from lib/util/util_strlist.c  */
#ifdef _SAMBA_BUILD_

/* separators for lists */
#ifndef LIST_SEP
#define LIST_SEP " \t,\n\r"
#endif

/**
  build a null terminated list of strings from a input string and a
  separator list. The separator list must contain characters less than
  or equal to 0x2f for this to work correctly on multi-byte strings
*/
_PUBLIC_ char **str_list_make(TALLOC_CTX *mem_ctx, const char *string, const char *sep);

/**
 * build a null terminated list of strings from an argv-like input string 
 * Entries are seperated by spaces and can be enclosed by quotes. 
 * Does NOT support escaping
 */
_PUBLIC_ const char **str_list_make_shell(TALLOC_CTX *mem_ctx, const char *string, const char *sep);

/**
 * join a list back to one string 
 */
_PUBLIC_ char *str_list_join(TALLOC_CTX *mem_ctx, const char **list, char seperator);

/** join a list back to one (shell-like) string; entries 
 * seperated by spaces, using quotes where necessary */
_PUBLIC_ char *str_list_join_shell(TALLOC_CTX *mem_ctx, const char **list, char sep);

/**
  return the number of elements in a string list
*/
_PUBLIC_ size_t str_list_length(const char * const *list);

/**
  copy a string list
*/
_PUBLIC_ char **str_list_copy(TALLOC_CTX *mem_ctx, const char **list);

/**
   Return true if all the elements of the list match exactly.
 */
_PUBLIC_ bool str_list_equal(const char **list1, const char **list2);

/**
  add an entry to a string list
*/
_PUBLIC_ const char **str_list_add(const char **list, const char *s);

/**
  remove an entry from a string list
*/
_PUBLIC_ void str_list_remove(const char **list, const char *s);

/**
  return true if a string is in a list
*/
_PUBLIC_ bool str_list_check(const char **list, const char *s);

/**
  return true if a string is in a list, case insensitively
*/
_PUBLIC_ bool str_list_check_ci(const char **list, const char *s);
#endif

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


#ifdef _SAMBA_BUILD_
/**
read a line from a file with possible \ continuation chars. 
Blanks at the start or end of a line are stripped.
The string will be allocated if s2 is NULL
**/
_PUBLIC_ char *fgets_slash(char *s2,int maxlen,XFILE *f);
#endif

/**
 * Read one line (data until next newline or eof) and allocate it 
 */
_PUBLIC_ char *afdgets(int fd, TALLOC_CTX *mem_ctx, size_t hint);

#ifdef _SAMBA_BUILD_
/**
load a file into memory from a fd.
**/
_PUBLIC_ char *fd_load(int fd, size_t *size, size_t maxsize, TALLOC_CTX *mem_ctx);


char **file_lines_parse(char *p, size_t size, int *numlines, TALLOC_CTX *mem_ctx);

/**
load a file into memory
**/
_PUBLIC_ char *file_load(const char *fname, size_t *size, size_t maxsize, TALLOC_CTX *mem_ctx);
#endif

/**
mmap (if possible) or read a file
**/
_PUBLIC_ void *map_file(const char *fname, size_t size);

#ifdef _SAMBA_BUILD_
/**
load a file into memory and return an array of pointers to lines in the file
must be freed with talloc_free(). 
**/
_PUBLIC_ char **file_lines_load(const char *fname, int *numlines, size_t maxsize, TALLOC_CTX *mem_ctx);
#endif

/**
load a fd into memory and return an array of pointers to lines in the file
must be freed with talloc_free(). If convert is true calls unix_to_dos on
the list.
**/
_PUBLIC_ char **fd_lines_load(int fd, int *numlines, size_t maxsize, TALLOC_CTX *mem_ctx);

/**
take a list of lines and modify them to produce a list where \ continues
a line
**/
_PUBLIC_ void file_lines_slashcont(char **lines);

/**
  save a lump of data into a file. Mostly used for debugging 
*/
_PUBLIC_ bool file_save(const char *fname, const void *packet, size_t length);
_PUBLIC_ int vfdprintf(int fd, const char *format, va_list ap) PRINTF_ATTRIBUTE(2,0);
_PUBLIC_ int fdprintf(int fd, const char *format, ...) PRINTF_ATTRIBUTE(2,3);
_PUBLIC_ bool large_file_support(const char *path);

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


/**
 Find a suitable temporary directory. The result should be copied immediately
 as it may be overwritten by a subsequent call.
**/
_PUBLIC_ const char *tmpdir(void);

/**
 Check if a file exists - call vfs_file_exist for samba files.
**/
_PUBLIC_ bool file_exist(const char *fname);

/**
 Check a files mod time.
**/
_PUBLIC_ time_t file_modtime(const char *fname);

/**
 Check if a directory exists.
**/
_PUBLIC_ bool directory_exist(const char *dname);

/**
 * Try to create the specified directory if it didn't exist.
 *
 * @retval true if the directory already existed and has the right permissions 
 * or was successfully created.
 */
_PUBLIC_ bool directory_create_or_exist(const char *dname, uid_t uid, 
                               mode_t dir_perms);

/**
 Set a fd into blocking/nonblocking mode. Uses POSIX O_NONBLOCK if available,
 else
  if SYSV use O_NDELAY
  if BSD use FNDELAY
**/
_PUBLIC_ int set_blocking(int fd, bool set);

/**
 Sleep for a specified number of milliseconds.
**/
_PUBLIC_ void msleep(unsigned int t);

/**
 Get my own name, return in malloc'ed storage.
**/
_PUBLIC_ char* get_myname(void);

/**
 Return true if a string could be a pure IP address.
**/
_PUBLIC_ bool is_ipaddress(const char *str);

/**
 Interpret an internet address or name into an IP address in 4 byte form.
**/
_PUBLIC_ uint32_t interpret_addr(const char *str);

/**
 A convenient addition to interpret_addr().
**/
_PUBLIC_ struct in_addr interpret_addr2(const char *str);

/**
 Check if an IP is the 0.0.0.0.
**/
_PUBLIC_ bool is_zero_ip_v4(struct in_addr ip);

/**
 Are two IPs on the same subnet?
**/
_PUBLIC_ bool same_net_v4(struct in_addr ip1,struct in_addr ip2,struct in_addr mask);

_PUBLIC_ bool is_ipaddress_v4(const char *str);

/**
 Check if a process exists. Does this work on all unixes?
**/
_PUBLIC_ bool process_exists_by_pid(pid_t pid);

/**
 Simple routine to do POSIX file locking. Cruft in NFS and 64->32 bit mapping
 is dealt with in posix.c
**/
_PUBLIC_ bool fcntl_lock(int fd, int op, off_t offset, off_t count, int type);

/**
 malloc that aborts with smb_panic on fail or zero size.
**/
_PUBLIC_ void *smb_xmalloc(size_t size);

/**
 Memdup with smb_panic on fail.
**/
_PUBLIC_ void *smb_xmemdup(const void *p, size_t size);

/**
 strdup that aborts on malloc fail.
**/
_PUBLIC_ char *smb_xstrdup(const char *s);

char *smb_xstrndup(const char *s, size_t n);

/**
 Like strdup but for memory.
**/
_PUBLIC_ void *memdup(const void *p, size_t size);

/**
 * see if a range of memory is all zero. A NULL pointer is considered
 * to be all zero 
 */
_PUBLIC_ bool all_zero(const uint8_t *ptr, size_t size);

/**
  realloc an array, checking for integer overflow in the array size
*/
_PUBLIC_ void *realloc_array(void *ptr, size_t el_size, unsigned count, bool free_on_fail);

void *malloc_array(size_t el_size, unsigned int count);

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


/**
 * Retrieve amount of free disk space.
 * this does all of the system specific guff to get the free disk space.
 * It is derived from code in the GNU fileutils package, but has been
 * considerably mangled for use here 
 *
 * results are returned in *dfree and *dsize, in 512 byte units
*/
_PUBLIC_ int sys_fsusage(const char *path, uint64_t *dfree, uint64_t *dsize);

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


/**
 * @file
 * @brief MS-style Filename matching
 */

#if _SAMBA_BUILD_ == 4
/* protocol types. It assumes that higher protocols include lower protocols
   as subsets. FIXME: Move to one of the smb-specific headers */
enum protocol_types {
        PROTOCOL_NONE,
        PROTOCOL_CORE,
        PROTOCOL_COREPLUS,
        PROTOCOL_LANMAN1,
        PROTOCOL_LANMAN2,
        PROTOCOL_NT1,
        PROTOCOL_SMB2
};

int ms_fnmatch(const char *pattern, const char *string, enum protocol_types protocol);

/** a generic fnmatch function - uses for non-CIFS pattern matching */
int gen_fnmatch(const char *pattern, const char *string);
#endif

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


#ifdef _SAMBA_BUILD_
/**
  register a set of mutex/rwlock handlers. 
  Should only be called once in the execution of smbd.
*/
_PUBLIC_ bool register_mutex_handlers(const char *name, struct mutex_ops *ops);
#endif

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


/**
  initialise a idr tree. The context return value must be passed to
  all subsequent idr calls. To destroy the idr tree use talloc_free()
  on this context
 */
_PUBLIC_ struct idr_context *idr_init(TALLOC_CTX *mem_ctx);

/**
  allocate the next available id, and assign 'ptr' into its slot.
  you can retrieve later this pointer using idr_find()
*/
_PUBLIC_ int idr_get_new(struct idr_context *idp, void *ptr, int limit);

/**
   allocate a new id, giving the first available value greater than or
   equal to the given starting id
*/
_PUBLIC_ int idr_get_new_above(struct idr_context *idp, void *ptr, int starting_id, int limit);

/**
  allocate a new id randomly in the given range
*/
_PUBLIC_ int idr_get_new_random(struct idr_context *idp, void *ptr, int limit);

/**
  find a pointer value previously set with idr_get_new given an id
*/
_PUBLIC_ void *idr_find(struct idr_context *idp, int id);

/**
  remove an id from the idr tree
*/
_PUBLIC_ int idr_remove(struct idr_context *idp, int id);

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

#if _SAMBA_BUILD_ == 4
/**
 Become a daemon, discarding the controlling terminal.
**/
_PUBLIC_ void become_daemon(bool fork);
#endif

/**
 * Load a ini-style file.
 */
bool pm_process( const char *fileName,
                 bool (*sfunc)(const char *, void *),
                 bool (*pfunc)(const char *, const char *, void *),
                                 void *userdata);

/**
 * Add-on to talloc_get_type
 */
_PUBLIC_ void *talloc_check_name_abort(const void *ptr, const char *name);
#define talloc_get_type_abort(ptr, type) \
        (type *)talloc_check_name_abort(ptr, #type)

bool unmap_file(void *start, size_t size);

#define CONST_DISCARD(type, ptr)      ((type) ((void *) (ptr)))

#endif /* _SAMBA_UTIL_H_ */