pread_write.c 3.6 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112
  1. /* vi: set sw=4 ts=4:
  2. *
  3. * Copyright (C) 2002 by Erik Andersen <andersen@uclibc.org>
  4. * Based in part on the files
  5. * ./sysdeps/unix/sysv/linux/pwrite.c,
  6. * ./sysdeps/unix/sysv/linux/pread.c,
  7. * sysdeps/posix/pread.c
  8. * sysdeps/posix/pwrite.c
  9. * from GNU libc 2.2.5, but reworked considerably...
  10. *
  11. * This program is free software; you can redistribute it and/or modify it
  12. * under the terms of the GNU Library General Public License as published by
  13. * the Free Software Foundation; either version 2 of the License, or (at your
  14. * option) any later version.
  15. *
  16. * This program is distributed in the hope that it will be useful, but WITHOUT
  17. * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  18. * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License
  19. * for more details.
  20. *
  21. * You should have received a copy of the GNU Library General Public License
  22. * along with this program; if not, write to the Free Software Foundation,
  23. * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  24. */
  25. #define _GNU_SOURCE
  26. #define _LARGEFILE64_SOURCE
  27. #include <features.h>
  28. #undef __OPTIMIZE__
  29. /* We absolutely do _NOT_ want interfaces silently
  30. * * * renamed under us or very bad things will happen... */
  31. #ifdef __USE_FILE_OFFSET64
  32. # undef __USE_FILE_OFFSET64
  33. #endif
  34. #include <errno.h>
  35. #include <sys/types.h>
  36. #include <sys/syscall.h>
  37. #include <unistd.h>
  38. #include <stdint.h>
  39. #ifdef __NR_pread64 /* Newer kernels renamed but it's the same. */
  40. # ifdef __NR_pread
  41. # error "__NR_pread and __NR_pread64 both defined???"
  42. # endif
  43. # define __NR_pread __NR_pread64
  44. #endif
  45. #ifdef __NR_pread
  46. #ifdef __mips64
  47. _syscall4(ssize_t, pread, int, fd, void *, buf, size_t, count, off_t, offset);
  48. #else /* !__mips64 */
  49. #define __NR___syscall_pread __NR_pread
  50. static inline _syscall6(ssize_t, __syscall_pread, int, fd, void *, buf,
  51. size_t, count, int, dummy, off_t, offset_hi, off_t, offset_lo);
  52. ssize_t __libc_pread(int fd, void *buf, size_t count, off_t offset)
  53. {
  54. return(__syscall_pread(fd,buf,count,0,__LONG_LONG_PAIR(offset>>31,offset)));
  55. }
  56. weak_alias (__libc_pread, pread)
  57. #if defined __UCLIBC_HAS_LFS__
  58. ssize_t __libc_pread64(int fd, void *buf, size_t count, off64_t offset)
  59. {
  60. uint32_t low = offset & 0xffffffff;
  61. uint32_t high = offset >> 32;
  62. return(__syscall_pread(fd, buf, count, 0, __LONG_LONG_PAIR (high, low)));
  63. }
  64. weak_alias (__libc_pread64, pread64)
  65. #endif /* __UCLIBC_HAS_LFS__ */
  66. #endif /* !__mips64 */
  67. #endif /* __NR_pread */
  68. /**********************************************************************/
  69. #ifdef __NR_pwrite64 /* Newer kernels renamed but it's the same. */
  70. # ifdef __NR_pwrite
  71. # error "__NR_pwrite and __NR_pwrite64 both defined???"
  72. # endif
  73. # define __NR_pwrite __NR_pwrite64
  74. #endif
  75. #ifdef __NR_pwrite
  76. #ifdef __mips64
  77. _syscall4(ssize_t, pwrite, int, fd, const void *, buf, size_t, count, off_t, offset);
  78. #else /* !__mips64 */
  79. #define __NR___syscall_pwrite __NR_pwrite
  80. static inline _syscall6(ssize_t, __syscall_pwrite, int, fd, const void *, buf,
  81. size_t, count, int, dummy, off_t, offset_hi, off_t, offset_lo);
  82. ssize_t __libc_pwrite(int fd, const void *buf, size_t count, off_t offset)
  83. {
  84. return(__syscall_pwrite(fd,buf,count,0,__LONG_LONG_PAIR(offset>>31,offset)));
  85. }
  86. weak_alias (__libc_pwrite, pwrite)
  87. #if defined __UCLIBC_HAS_LFS__
  88. ssize_t __libc_pwrite64(int fd, const void *buf, size_t count, off64_t offset)
  89. {
  90. uint32_t low = offset & 0xffffffff;
  91. uint32_t high = offset >> 32;
  92. return(__syscall_pwrite(fd, buf, count, 0, __LONG_LONG_PAIR (high, low)));
  93. }
  94. weak_alias (__libc_pwrite64, pwrite64)
  95. #endif /* __UCLIBC_HAS_LFS__ */
  96. #endif /* !__mips64 */
  97. #endif /* __NR_pwrite */