src/include/gpxe/posix_io.h

   1 #ifndef _GPXE_POSIX_IO_H
   2 #define _GPXE_POSIX_IO_H
   3
   4 /** @file
   5  *
   6  * POSIX-like I/O
   7  *
   8  */
   9
  10 #include <stdint.h>
  11 #include <gpxe/uaccess.h>
  12
  13 /** Minimum file descriptor that will ever be allocated */
  14 #define POSIX_FD_MIN ( 1 )
  15
  16 /** Maximum file descriptor that will ever be allocated */
  17 #define POSIX_FD_MAX ( 31 )
  18
  19 /** File descriptor set as used for select() */
  20 typedef uint32_t fd_set;
  21
  22 extern int open ( const char *uri_string );
  23 extern ssize_t read_user ( int fd, userptr_t buffer,
  24                            off_t offset, size_t len );
  25 extern int select ( fd_set *readfds, int wait );
  26 extern ssize_t fsize ( int fd );
  27 extern int close ( int fd );
  28
  29 /**
  30  * Zero a file descriptor set
  31  *
  32  * @v set               File descriptor set
  33  */
  34 static inline __attribute__ (( always_inline )) void
  35 FD_ZERO ( fd_set *set ) {
  36         *set = 0;
  37 }
  38
  39 /**
  40  * Set a bit within a file descriptor set
  41  *
  42  * @v fd                File descriptor
  43  * @v set               File descriptor set
  44  */
  45 static inline __attribute__ (( always_inline )) void
  46 FD_SET ( int fd, fd_set *set ) {
  47         *set |= ( 1 << fd );
  48 }
  49
  50 /**
  51  * Clear a bit within a file descriptor set
  52  *
  53  * @v fd                File descriptor
  54  * @v set               File descriptor set
  55  */
  56 static inline __attribute__ (( always_inline )) void
  57 FD_CLR ( int fd, fd_set *set ) {
  58         *set &= ~( 1 << fd );
  59 }
  60
  61 /**
  62  * Test a bit within a file descriptor set
  63  *
  64  * @v fd                File descriptor
  65  * @v set               File descriptor set
  66  * @ret is_set          Corresponding bit is set
  67  */
  68 static inline __attribute__ (( always_inline )) int
  69 FD_ISSET ( int fd, fd_set *set ) {
  70         return ( *set & ( 1 << fd ) );
  71 }
  72
  73 /**
  74  * Read data from file
  75  *
  76  * @v fd                File descriptor
  77  * @v buf               Data buffer
  78  * @v len               Maximum length to read
  79  * @ret len             Actual length read, or negative error number
  80  */
  81 static inline ssize_t read ( int fd, void *buf, size_t len ) {
  82         return read_user ( fd, virt_to_user ( buf ), 0, len );
  83 }
  84
  85 #endif /* _GPXE_POSIX_IO_H */