pipe.c

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#include "default.h"
#include "io.h"
#include <lely/io/pipe.h>

#if defined(_WIN32) || _POSIX_C_SOURCE >= 200112L

#ifdef _WIN32
#include <lely/libc/stdio.h>

#ifdef __MINGW32__
// Ignore complaints that "I64" is not a valid ISO C length modifier.
#pragma GCC diagnostic ignored "-Wformat"
#pragma GCC diagnostic ignored "-Wformat-extra-args"
#endif

static int pipe(HANDLE fildes[2]);
#endif

static const struct io_handle_vtab pipe_vtab = { .type = IO_TYPE_PIPE,
        .size = sizeof(struct io_handle),
        .fini = &default_fini,
        .flags = &default_flags,
        .read = &default_read,
        .write = &default_write };

int
io_open_pipe(io_handle_t handle_vector[2])
{
        assert(handle_vector);
        handle_vector[0] = handle_vector[1] = IO_HANDLE_ERROR;

        int errc = 0;

#ifdef _WIN32
        HANDLE fd[2];
#else
        int fd[2];
#endif
#if defined(__CYGWIN__) || defined(__linux__)
        if (__unlikely(pipe2(fd, O_CLOEXEC) == -1)) {
#else
        if (__unlikely(pipe(fd) == -1)) {
#endif
                errc = get_errc();
                goto error_pipe;
        }

#if _POSIX_C_SOURCE >= 200112L && !defined(__CYGINW__) && !defined(__linux__)
        if (__unlikely(fcntl(fd[0], F_SETFD, FD_CLOEXEC) == -1)) {
                errc = get_errc();
                goto error_fcntl;
        }
        if (__unlikely(fcntl(fd[1], F_SETFD, FD_CLOEXEC) == -1)) {
                errc = get_errc();
                goto error_fcntl;
        }
#endif

        handle_vector[0] = io_handle_alloc(&pipe_vtab);
        if (__unlikely(!handle_vector[0])) {
                errc = get_errc();
                goto error_alloc_handle_vector_0;
        }
        handle_vector[0]->fd = fd[0];

        handle_vector[1] = io_handle_alloc(&pipe_vtab);
        if (__unlikely(!handle_vector[1])) {
                errc = get_errc();
                goto error_alloc_handle_vector_1;
        }
        handle_vector[1]->fd = fd[1];

        io_handle_acquire(handle_vector[0]);
        io_handle_acquire(handle_vector[1]);

        return 0;

error_alloc_handle_vector_1:
        handle_vector[1] = IO_HANDLE_ERROR;
        io_handle_free(handle_vector[0]);
error_alloc_handle_vector_0:
        handle_vector[0] = IO_HANDLE_ERROR;
#if _POSIX_C_SOURCE >= 200112L && !defined(__CYGINW__) && !defined(__linux__)
error_fcntl:
#endif
#ifdef _WIN32
        CloseHandle(fd[1]);
        CloseHandle(fd[0]);
#else
        close(fd[1]);
        close(fd[0]);
#endif
error_pipe:
        set_errc(errc);
        return -1;
}

#ifdef _WIN32
static int
pipe(HANDLE fildes[2])
{
        assert(fildes);
        fildes[0] = fildes[1] = INVALID_HANDLE_VALUE;

        DWORD dwErrCode = 0;

        CHAR Name[MAX_PATH] = { 0 };
        static LONGLONG cnt;
        snprintf(Name, sizeof(Name) - 1,
                        "\\\\.\\pipe\\lely-io-pipe-%04lx-%08I64x",
                        GetCurrentProcessId(), InterlockedIncrement64(&cnt));

        fildes[0] = CreateNamedPipeA(Name,
                        PIPE_ACCESS_INBOUND | FILE_FLAG_OVERLAPPED,
                        PIPE_TYPE_BYTE | PIPE_WAIT, 1, 1, 1, 0, NULL);
        if (__unlikely(fildes[0] == INVALID_HANDLE_VALUE)) {
                dwErrCode = GetLastError();
                goto error_CreateNamedPipeA;
        }

        fildes[1] = CreateFileA(Name, GENERIC_WRITE, 0, NULL, OPEN_EXISTING,
                        FILE_ATTRIBUTE_NORMAL | FILE_FLAG_OVERLAPPED, NULL);
        if (__unlikely(fildes[1] == INVALID_HANDLE_VALUE)) {
                dwErrCode = GetLastError();
                goto error_CreateFileA;
        }

        return 0;

error_CreateFileA:
        CloseHandle(fildes[0]);
        fildes[0] = INVALID_HANDLE_VALUE;
error_CreateNamedPipeA:
        SetLastError(dwErrCode);
        return -1;
}
#endif

#endif // _WIN32 || _POSIX_C_SOURCE >= 200112L