CRYPTO_LOCK(3)             Library Functions Manual             CRYPTO_LOCK(3)

NAME
     CRYPTO_lock, CRYPTO_w_lock, CRYPTO_w_unlock, CRYPTO_r_lock,
     CRYPTO_r_unlock, CRYPTO_add - thread support

SYNOPSIS
     #include <openssl/crypto.h>

     void
     CRYPTO_lock(int mode, int type, const char *file, int line);

     int
     CRYPTO_add(int *p, int amount, int type);

     #define CRYPTO_w_lock(type) \
             CRYPTO_lock(CRYPTO_LOCK|CRYPTO_WRITE, type, __FILE__, __LINE__)
     #define CRYPTO_w_unlock(type) \
             CRYPTO_lock(CRYPTO_UNLOCK|CRYPTO_WRITE, type, __FILE__, __LINE__)
     #define CRYPTO_r_lock(type) \
             CRYPTO_lock(CRYPTO_LOCK|CRYPTO_READ, type, __FILE__, __LINE__)
     #define CRYPTO_r_unlock(type) \
             CRYPTO_lock(CRYPTO_UNLOCK|CRYPTO_READ, type, __FILE__, __LINE__)

DESCRIPTION
     These functions are obsolete.  CRYPTO_lock() locks or unlocks a mutex
     lock.

     mode is a bitfield describing what should be done with the lock.  For
     each call, either CRYPTO_LOCK or CRYPTO_UNLOCK must be included.  In the
     LibreSSL implementation, CRYPTO_READ and CRYPTO_WRITE are ignored.

     type is a number in the range 0 <= type < CRYPTO_NUM_LOCKS identifying a
     particular lock.  Currently, the value of CRYPTO_NUM_LOCKS is 41.

     The file and line arguments are ignored.

     In the LibreSSL implementation, CRYPTO_lock() is a wrapper around
     pthread_mutex_lock(3) and pthread_mutex_unlock(3).

     CRYPTO_add() locks the lock number type, adds amount to *p, and unlocks
     the lock number type again.

RETURN VALUES
     CRYPTO_add() returns the new value of *p.

SEE ALSO
     crypto(3)

HISTORY
     CRYPTO_lock(), CRYPTO_w_lock(), CRYPTO_w_unlock(), CRYPTO_r_lock(), and
     CRYPTO_r_unlock() first appeared in SSLeay 0.6.0.  CRYPTO_add() first
     appeared in SSLeay 0.6.2.  These functions have been available since
     OpenBSD 2.4.

Linux 6.8.2-arch2-1              March 4, 2024             Linux 6.8.2-arch2-1