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- /** @file io.c
- * @brief Enchanced base IO functions.
- */
- #include <stdlib.h>
- #include <unistd.h>
- #include <assert.h>
- #include <errno.h>
- #include <stdio.h>
- #include <sys/types.h>
- #include <sys/socket.h>
- #include <sys/uio.h>
- #include <sys/stat.h>
- #include <fcntl.h>
- #include "faux/faux.h"
- /** @brief Writes data to file.
- *
- * The system write() can be interrupted by signal. This function will retry to
- * write in a case of interrupted call.
- *
- * @param [in] fd File descriptor.
- * @param [in] buf Buffer to write.
- * @param [in] n Number of bytes to write.
- * @return Number of bytes written or < 0 on error.
- */
- ssize_t faux_write(int fd, const void *buf, size_t n)
- {
- ssize_t bytes_written = 0;
- assert(fd != -1);
- assert(buf);
- if ((-1 == fd) || !buf)
- return -1;
- if (0 == n)
- return 0;
- do {
- bytes_written = write(fd, buf, n);
- } while ((bytes_written < 0) && (EINTR == errno));
- return bytes_written;
- }
- /** @brief Writes data block to file.
- *
- * The system write() can be interrupted by signal or can write less bytes
- * than specified. This function will continue to write data until all data
- * will be written or error occured.
- *
- * @param [in] fd File descriptor.
- * @param [in] buf Buffer to write.
- * @param [in] n Number of bytes to write.
- * @return Number of bytes written.
- * < n then insufficient space or error (but some data was already written).
- * < 0 - error.
- */
- ssize_t faux_write_block(int fd, const void *buf, size_t n)
- {
- ssize_t bytes_written = 0;
- size_t total_written = 0;
- size_t left = n;
- const void *data = buf;
- do {
- bytes_written = faux_write(fd, data, left);
- if (bytes_written < 0) { // Error
- if (total_written != 0)
- return total_written;
- return -1;
- }
- if (0 == bytes_written) // Insufficient space
- return total_written;
- data += bytes_written;
- left = left - bytes_written;
- total_written += bytes_written;
- } while (left > 0);
- return total_written;
- }
- /** @brief Reads data from file.
- *
- * The system read() can be interrupted by signal. This function will retry to
- * read if it was interrupted by signal.
- *
- * @param [in] fd File descriptor.
- * @param [in] buf Buffer to write.
- * @param [in] n Number of bytes to write.
- * @return Number of bytes readed or < 0 on error.
- * 0 bytes indicates EOF
- */
- ssize_t faux_read(int fd, void *buf, size_t n)
- {
- ssize_t bytes_readed = 0;
- assert(fd != -1);
- assert(buf);
- if ((-1 == fd) || !buf)
- return -1;
- if (0 == n)
- return 0;
- do {
- bytes_readed = read(fd, buf, n);
- } while ((bytes_readed < 0) && (EINTR == errno));
- return bytes_readed;
- }
- /** @brief Reads data block from file.
- *
- * The system read() can be interrupted by signal or can read less bytes
- * than specified. This function will continue to read data until all data
- * will be readed or error occured.
- *
- * @param [in] fd File descriptor.
- * @param [in] buf Buffer to write.
- * @param [in] n Number of bytes to write.
- * @return Number of bytes readed.
- * < n EOF or error (but some data was already readed).
- * < 0 Error.
- */
- size_t faux_read_block(int fd, void *buf, size_t n)
- {
- ssize_t bytes_readed = 0;
- size_t total_readed = 0;
- size_t left = n;
- void *data = buf;
- do {
- bytes_readed = read(fd, data, left);
- if (bytes_readed < 0) {
- if (total_readed != 0)
- return total_readed;
- return -1;
- }
- if (0 == bytes_readed) // EOF
- return total_readed;
- data += bytes_readed;
- left = left - bytes_readed;
- total_readed += bytes_readed;
- } while (left > 0);
- return total_readed;
- }
- /** @brief Reads whole file to buffer.
- *
- * Allocates buffer and read whole file to it.
- *
- * @param [in] path File name.
- * @param [out] buf Output buffer with file content.
- * @warn Buffer must be freed with faux_free().
- * @return Number of bytes readed.
- * = n Empty file. The data param will be set to NULL.
- * < 0 Error.
- */
- ssize_t faux_read_whole_file(const char *path, void **data)
- {
- ssize_t expected_size = 0;
- struct stat statbuf = {};
- char *buf = NULL;
- size_t buf_full_size = 0;
- ssize_t bytes_readed = 0;
- size_t total_readed = 0;
- int fd = -1;
- assert(path);
- assert(data);
- if (!path || !data)
- return -1;
- if (stat(path, &statbuf) < 0)
- return -1;
- // Regular file?
- if (!S_ISREG(statbuf.st_mode))
- return -1;
- // Get expected file size
- expected_size = faux_filesize(path);
- if (expected_size < 0)
- return -1;
- // Add some extra space to buffer. Because actual filesize can
- // differ while reading. Try to read more data than expected.
- expected_size++;
- // Open file
- fd = open(path, O_RDONLY);
- if (fd < 0)
- return -1;
- // Allocate buffer
- buf_full_size = expected_size;
- buf = faux_zmalloc(buf_full_size);
- if (!buf) {
- close(fd);
- return -1;
- }
- while ((bytes_readed = faux_read(fd, buf + total_readed,
- buf_full_size - total_readed)) > 0) {
- total_readed += bytes_readed;
- // Enlarge buffer if needed
- if (total_readed == buf_full_size) {
- char *p = NULL;
- buf_full_size = buf_full_size * 2;
- p = realloc(buf, buf_full_size);
- if (!p) {
- free(buf);
- close(fd);
- return -1;
- }
- buf = p;
- }
- }
- close(fd);
- // Something went wrong
- if (bytes_readed < 0) {
- free(buf);
- return -1;
- }
- // Empty file
- if (0 == total_readed) {
- free(buf);
- *data = NULL;
- return 0;
- }
- // Shrink buffer to actual data size
- if (total_readed < buf_full_size) {
- char *p = NULL;
- p = realloc(buf, total_readed);
- if (!p) {
- free(buf);
- return -1;
- }
- buf = p;
- }
- *data = buf;
- return total_readed;
- }
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