diff options
-rw-r--r-- | sys/include/sys/limits.h | 1 | ||||
-rw-r--r-- | sys/include/sys/uio.h | 51 | ||||
-rw-r--r-- | sys/kern/kern_uio.c | 156 |
3 files changed, 208 insertions, 0 deletions
diff --git a/sys/include/sys/limits.h b/sys/include/sys/limits.h index 963d113..c0ce5af 100644 --- a/sys/include/sys/limits.h +++ b/sys/include/sys/limits.h @@ -38,4 +38,5 @@ #define CPU_MAX 256 #define VSR_MAX_DOMAIN 16 #define VSR_MAX_CAPSULE 16 +#define IOVEC_MAX 512 #endif /* !_SYS_LIMITS_H_ */ diff --git a/sys/include/sys/uio.h b/sys/include/sys/uio.h new file mode 100644 index 0000000..d1d4c65 --- /dev/null +++ b/sys/include/sys/uio.h @@ -0,0 +1,51 @@ +/* + * Copyright (c) 2023-2025 Ian Marco Moffett and the Osmora Team. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of Hyra nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#ifndef _SYS_UIO_H_ +#define _SYS_UIO_H_ + +#if defined(_KERNEL) +#include <sys/types.h> +#else +#include <stdint.h> +#include <stddef.h> +#endif /* _KERNEL */ + +/* + * POSIX I/O vector + */ +struct iovec { + void *iov_base; + size_t iov_len; +}; + +ssize_t readv(int filedes, const struct iovec *iov, int iovcnt); +ssize_t writev(int filedes, const struct iovec *iov, int iovcnt); + +#endif /* !_SYS_UIO_H_ */ diff --git a/sys/kern/kern_uio.c b/sys/kern/kern_uio.c new file mode 100644 index 0000000..dd533c2 --- /dev/null +++ b/sys/kern/kern_uio.c @@ -0,0 +1,156 @@ +/* + * Copyright (c) 2023-2025 Ian Marco Moffett and the Osmora Team. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of Hyra nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#include <sys/limits.h> +#include <sys/errno.h> +#include <sys/types.h> +#include <sys/uio.h> +#include <sys/filedesc.h> + +/* + * Read data into POSIX.1‐2017 iovec + * + * @filedes: File descriptor number + * @iov: I/O vector to read file into + * @iovnt: Number of I/O vectors + */ +ssize_t +readv(int filedes, const struct iovec *iov, int iovcnt) +{ + void *base; + size_t len; + ssize_t tmp, bytes_read = 0; + + if (filedes < 0) { + return -EINVAL; + } + + /* + * Make sure that this conforms to our max + * iovec limit. + */ + if (iovcnt > IOVEC_MAX) { + return -EINVAL; + } + + /* + * Go through each I/O vector and read a chunk + * of data into one. + */ + for (int i = 0; i < iovcnt; ++i) { + base = iov[i].iov_base; + len = iov[i].iov_len; + + /* + * If we encounter a base that is NULL, + * or if the length to read is an invalid + * value of zero. We can just assume this + * is some sort of weird list termination? + */ + if (base == NULL || len == 0) { + break; + } + + /* Read the file into this base */ + tmp = fd_read(filedes, base, len); + + /* Did anything go wrong? */ + if (tmp < 0) { + return tmp; + } + + /* No more data */ + if (tmp == 0) { + break; + } + + /* Read more bytes */ + bytes_read += tmp; + } + + return bytes_read; +} + +/* + * Write data from POSIX.1‐2017 iovec + * + * @filedes: File descriptor number + * @iov: I/O vector to write to file + * @iovnt: Number of I/O vectors + */ +ssize_t +writev(int filedes, const struct iovec *iov, int iovcnt) +{ + void *base; + size_t len; + ssize_t bytes_written = 0; + ssize_t tmp; + + if (filedes < 0) { + return -EINVAL; + } + + /* + * Are we within the limits? Return an + * error if not. + */ + if (iovcnt > IOVEC_MAX) { + return -EINVAL; + } + + for (int i = 0; i < iovcnt; ++i) { + base = iov[i].iov_base; + len = iov[i].iov_len; + + /* + * These are invalid, whatever these are, + * terminate our walk through. + */ + if (base == NULL || len == 0) { + break; + } + + /* Write the data from the iovec */ + tmp = fd_write(filedes, base, len); + + /* Was there an error? */ + if (tmp < 0) { + return tmp; + } + + /* No more data to read? */ + if (tmp == 0) { + break; + } + + bytes_written += tmp; + } + + return bytes_written; +} |