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- /** @file file.c
- * @brief Functions for working with files.
- *
- * This library was created to exclude glibc's file stream operations like
- * fopen(), fgets() etc. These functions use glibc internal buffer. To work
- * with buffer glibc has its own fflush() function and special behaviour while
- * fclose(). It brings a problems with stream file objects and system file
- * descriptors while fork(). The file streams and system file descriptors can't
- * be used interchangeably. So faux file library uses standard system file
- * operations like open(), read() and emulate some usefull stream function like
- * getline(). The faux file object has own buffer and doesn't use glibc's one.
- * The faux_file_close() doesn't lseek() file descriptor as fclose() can do.
- * You can use faux file object and standard file operation in the same time.
- * The only thing to remember is internal buffer that can contain already
- * readed bytes.
- */
- #include <stdlib.h>
- #include <sys/types.h>
- #include <sys/stat.h>
- #include <fcntl.h>
- #include <unistd.h>
- #include <string.h>
- #include <assert.h>
- #include "private.h"
- #include "faux/faux.h"
- #include "faux/file.h"
- #include "faux/str.h"
- /** @brief Create file object using existent fd.
- *
- * Create file object an link it to existent file descriptor.
- *
- * @return Allocated and initialized file object or NULL on error.
- */
- faux_file_t *faux_file_fdopen(int fd) {
- struct stat stat_struct = {};
- faux_file_t *f = NULL;
- // Before object creation check is fd valid.
- // Try to get stat().
- if (fstat(fd, &stat_struct) < 0)
- return NULL; // Illegal fd
- f = faux_zmalloc(sizeof(*f));
- assert(f);
- if (!f)
- return NULL;
- // Init
- f->fd = fd;
- f->buf_size = FAUX_FILE_CHUNK_SIZE;
- f->buf = faux_zmalloc(f->buf_size);
- assert(f->buf);
- if (!f->buf) {
- faux_free(f);
- return NULL;
- }
- f->len = 0;
- return f;
- }
- faux_file_t *faux_file_open(const char *pathname, int flags, mode_t mode) {
- int fd = -1;
- assert(pathname);
- if (!pathname)
- return NULL;
- fd = open(pathname, flags, mode);
- if (fd < 0)
- return NULL;
- return faux_file_fdopen(fd);
- }
- int faux_file_close(faux_file_t *f) {
- int fd = -1;
- assert(f);
- if (!f)
- return -1;
- fd = f->fd;
- faux_free(f->buf);
- faux_free(f);
- return close(fd);
- }
- int faux_file_fileno(faux_file_t *f) {
- assert(f);
- if (!f)
- return -1;
- return f->fd;
- }
- static char *faux_file_takeaway_line(faux_file_t *f) {
- char *find = NULL;
- const char *eol = "\n\r";
- size_t line_len = 0;
- char *line = NULL;
- assert(f);
- if (!f)
- return NULL;
- find = faux_str_charsn(f->buf, eol, f->len);
- if (!find)
- return NULL; // End of line is not found
- line_len = find - f->buf;
- line = faux_str_dupn(f->buf, line_len);
- assert(line);
- if (!line)
- return NULL; // Memory problems
- // Remove line from the internal buffer
- // Remove EOL char also. So additional '1' is used
- f->len = f->len - line_len - 1;
- memmove(f->buf, find + 1, f->len);
- return line;
- }
- char *faux_file_getline(faux_file_t *f) {
- char *find = NULL;
- assert(f);
- if (!f)
- return NULL;
- // May be buffer already contain line
- find = faux_file_takeaway_line(f);
- if (find)
- return find;
- return NULL;
- }
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