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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-28 09:24:33 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-28 09:24:33 +0000 |
commit | 7a19c99f661602b67db95fd1d8aca5fe3a387441 (patch) | |
tree | 215ff04ec522779fa83acf394d296c2356c6b382 /lib/pread.h | |
parent | Initial commit. (diff) | |
download | pciutils-80b48659d5b3bdd36c7b3c9d0c0331ff0d08e44f.tar.xz pciutils-80b48659d5b3bdd36c7b3c9d0c0331ff0d08e44f.zip |
Adding upstream version 1:3.9.0.upstream/1%3.9.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/pread.h')
-rw-r--r-- | lib/pread.h | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/lib/pread.h b/lib/pread.h new file mode 100644 index 0000000..3db90e3 --- /dev/null +++ b/lib/pread.h @@ -0,0 +1,57 @@ +/* + * The PCI Library -- Portable interface to pread() and pwrite() + * + * Copyright (c) 1997--2003 Martin Mares <mj@ucw.cz> + * + * Can be freely distributed and used under the terms of the GNU GPL. + */ + +/* + * We'd like to use pread/pwrite for configuration space accesses, but + * unfortunately it isn't simple at all since all libc's until glibc 2.1 + * don't define it. + */ + +#if defined(__GLIBC__) && __GLIBC__ == 2 && __GLIBC_MINOR__ > 0 +/* glibc 2.1 or newer -> pread/pwrite supported automatically */ + +#elif defined(i386) && defined(__GLIBC__) +/* glibc 2.0 on i386 -> call syscalls directly */ +#include <asm/unistd.h> +#include <syscall-list.h> +#ifndef SYS_pread +#define SYS_pread 180 +#endif +static int pread(unsigned int fd, void *buf, size_t size, loff_t where) +{ return syscall(SYS_pread, fd, buf, size, where); } +#ifndef SYS_pwrite +#define SYS_pwrite 181 +#endif +static int pwrite(unsigned int fd, void *buf, size_t size, loff_t where) +{ return syscall(SYS_pwrite, fd, buf, size, where); } + +#else +/* In all other cases we use lseek/read/write instead to be safe */ +#define make_rw_glue(op) \ + static int do_##op(struct pci_dev *d, int fd, void *buf, size_t size, int where) \ + { \ + struct pci_access *a = d->access; \ + int r; \ + if (a->fd_pos != where && lseek(fd, where, SEEK_SET) < 0) \ + return -1; \ + r = op(fd, buf, size); \ + if (r < 0) \ + a->fd_pos = -1; \ + else \ + a->fd_pos = where + r; \ + return r; \ + } +make_rw_glue(read) +make_rw_glue(write) +#define PCI_HAVE_DO_READ +#endif + +#ifndef PCI_HAVE_DO_READ +#define do_read(d,f,b,l,p) pread(f,b,l,p) +#define do_write(d,f,b,l,p) pwrite(f,b,l,p) +#endif |