efl/src/lib/evil/evil_fcntl.h

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#ifndef __EVIL_FCNTL_H__
#define __EVIL_FCNTL_H__
# include <sys/types.h>
/**
* @def FD_CLOEXEC
* Specifies that the file descriptor should be closed when an exec()
* function is invoked.
*/
# define FD_CLOEXEC 1
/**
* @def O_NONBLOCK
* Specifies that the socket is in non-blocking mode.
*/
# define O_NONBLOCK 04000
/**
* @def F_SETFD
* Specifies that fcntl() should set the file descriptor flags
* associated with the filedes argument.
*/
/**
* @def F_SETLK
* Specifies that fcntl() should set or clear a file segment lock
* according to the lock description pointed to by the third argument.
*/
/**
* @def F_SETLKW
* Equivalent to F_SETLK except that if a shared or exclusive lock
* is blocked by other locks, the thread shall wait until the request
* can be satisfied.
*/
# define F_GETFD 1
# define F_SETFD 2
# define F_GETFL 3
# define F_SETFL 4
# define F_SETLK 6
# define F_SETLKW 7
/**
* @def F_RDLCK
* Read (or shared) lock
*/
/**
* @def F_WRLCK
* Write (or exclusive) lock
*/
/**
* @def F_UNLCK
* Remove lock
*/
# ifndef F_RDLCK
# define F_RDLCK 0
# define F_WRLCK 1
# define F_UNLCK 2
# endif /* ! F_RDLCK */
/**
* @struct flock
* @brief A structure that controls the lock of a file descriptor.
*/
struct flock
{
short int l_type; /**< lock type: read, write, ... */
short int l_whence; /**< type of l_start */
off_t l_start; /**< starting offset */
off_t l_len; /**< 0 means end of the file */
pid_t l_pid; /**< lock owner */
};
/**
* @brief Provide control over file descriptors.
*
* @param fd The file descriptor.
* @param cmd The type of control.
* @return 0 on success, -1 otherwise.
*
* Performs one of various miscellaneous operations on @p fd.
* The operation in question is determined by @p cmd:
*
* - F_SETFD: Set the close-on-exec flag to the value specified
* by the argument after command (only the least significant
* bit is used).
* - F_SETLK and F_SETLKW: used to manage discretionary file locks.
* The third argument must be a pointer to a struct flock (that
* may be overwritten by this call).
*
* This function returns 0 on success, -1 otherwise.
*
* Conformity: None.
*
* Supported OS: Windows Vista, Windows XP or Windows 2000
* Professional.
*
* @ingroup Evil
*/
evil: Rename EAPI macro to EVIL_API in Evil library Summary: Patch from a series of patches to rename EAPI symbols to specific library DSOs. EAPI was designed to be able to pass ```__attribute__ ((visibility ("default")))``` for symbols with GCC, which would mean that even if -fvisibility=hidden was used when compiling the library, the needed symbols would get exported. MSVC __almost__ works like GCC (or mingw) in which you can declare everything as export and it will just work (slower, but it will work). But there's a caveat: global variables will not work the same way for MSVC, but works for mingw and GCC. For global variables (as opposed to functions), MSVC requires correct DSO visibility for MSVC: instead of declaring a symbol as export for everything, you need to declare it as import when importing from another DSO and export when defining it locally. With current EAPI definitions, we get the following example working in mingw and MSVC (observe it doesn't define any global variables as exported symbols). ``` Example 1: dll1: ``` EAPI void foo(void); EAPI void bar() { foo(); } ``` dll2: ``` EAPI void foo() { printf ("foo\n"); } ``` This works fine with API defined as __declspec(dllexport) in both cases and for gcc defining as ```__atttribute__((visibility("default")))``` However, the following: Example 2: dll1: ``` EAPI extern int foo; EAPI void foobar(void); EAPI void bar() { foo = 5; foobar(); } ``` dll2: ``` EAPI int foo = 0; EAPI void foobar() { printf ("foo %d\n", foo); } ``` This will work on mingw but will not work for MSVC. And that's why EAPI is the only solution that worked for MSVC. Co-authored-by: João Paulo Taylor Ienczak Zanette <jpaulotiz@gmail.com> Co-authored-by: Ricardo Campos <ricardo.campos@expertise.dev> Co-authored-by: Lucas Cavalcante de Sousa <lucks.sousa@gmail.com> Reviewers: raster, vtorri, jptiz, lucas, woohyun Reviewed By: vtorri, jptiz Subscribers: ProhtMeyhet, cedric, #reviewers, #committers Tags: #efl Differential Revision: https://phab.enlightenment.org/D12182
2020-11-12 08:47:38 -08:00
EVIL_API int fcntl(int fd, int cmd, ...);
#endif /* __EVIL_FCNTL_H__ */