diff options
| -rw-r--r-- | inotail.c | 55 | ||||
| -rw-r--r-- | inotail.h | 2 |
2 files changed, 38 insertions, 19 deletions
@@ -30,7 +30,6 @@ #include <fcntl.h> #include <errno.h> #include <getopt.h> -#include <ctype.h> #include <sys/types.h> #include <sys/stat.h> @@ -94,11 +93,10 @@ static void usage(const int status) static inline void setup_file(struct file_struct *f) { - f->fd = -1; + f->fd = f->i_watch = -1; f->st_size = 0; f->st_blksize = DEFAULT_BUFFER_SIZE; f->ignore = 0; - f->i_watch = -1; } static void ignore_file(struct file_struct *f) @@ -145,7 +143,10 @@ static off_t lines_to_offset_from_end(struct file_struct *f, unsigned long n_lin /* Start of current block */ offset -= block_size; - lseek(f->fd, offset, SEEK_SET); + if (lseek(f->fd, offset, SEEK_SET) == (off_t) -1) { + fprintf(stderr, "Error: Could not seek in file '%s' (%s)\n", f->name, strerror(errno)); + return -1; + } rc = read(f->fd, buf, block_size); if (unlikely(rc < 0)) { @@ -184,7 +185,10 @@ static off_t lines_to_offset_from_begin(struct file_struct *f, unsigned long n_l int i; ssize_t rc, block_size = f->st_blksize; - lseek(f->fd, offset, SEEK_SET); + if (lseek(f->fd, offset, SEEK_SET) == (off_t) -1) { + fprintf(stderr, "Error: Could not seek in file '%s' (%s)\n", f->name, strerror(errno)); + return -1; + } rc = read(f->fd, buf, block_size); if (unlikely(rc < 0)) { @@ -226,10 +230,8 @@ static off_t bytes_to_offset(struct file_struct *f, unsigned long n_bytes) if (from_begin) { if (n_bytes > 0) offset = (off_t) n_bytes - 1; - } else { - if ((off_t) n_bytes < f->st_size) - offset = f->st_size - (off_t) n_bytes; - } + } else if ((off_t) n_bytes < f->st_size) + offset = f->st_size - (off_t) n_bytes; return offset; } @@ -244,7 +246,7 @@ static ssize_t tail_pipe(struct file_struct *f) /* We will just tail everything here */ while ((rc = read(f->fd, buf, f->st_blksize)) > 0) { - if (write(STDOUT_FILENO, buf, (size_t) rc) < 0) { + if (write(STDOUT_FILENO, buf, (size_t) rc) <= 0) { /* e.g. when writing to a pipe which gets closed */ fprintf(stderr, "Error: Could not write to stdout (%s)\n", strerror(errno)); rc = -1; @@ -310,7 +312,10 @@ static int tail_file(struct file_struct *f, unsigned long n_units, char mode, ch if (verbose) write_header(f->name); - lseek(f->fd, offset, SEEK_SET); + if (lseek(f->fd, offset, SEEK_SET) == (off_t) -1) { + fprintf(stderr, "Error: Could not seek in file '%s' (%s)\n", f->name, strerror(errno)); + return -1; + } while ((bytes_read = read(f->fd, buf, f->st_blksize)) > 0) write(STDOUT_FILENO, buf, (size_t) bytes_read); @@ -341,7 +346,13 @@ static int handle_inotify_event(struct inotify_event *inev, struct file_struct * if (verbose) write_header(f->name); - lseek(f->fd, f->st_size, SEEK_SET); /* Old file size */ + /* Seek to old file size */ + if (lseek(f->fd, f->st_size, SEEK_SET) == (off_t) -1) { + fprintf(stderr, "Error: Could not seek in file '%s' (%s)\n", f->name, strerror(errno)); + ret = -1; + goto ignore; + } + while ((rc = read(f->fd, fbuf, f->st_blksize)) != 0) write(STDOUT_FILENO, fbuf, (size_t) rc); @@ -377,10 +388,10 @@ static int watch_files(struct file_struct *files, int n_files) ifd = inotify_init(); if (errno == ENOSYS) { - fprintf(stderr, "Error: Inotify is not supported by the kernel you're currently running.\n"); + fprintf(stderr, "Error: inotify is not supported by the kernel you're currently running.\n"); exit(EXIT_FAILURE); } else if (unlikely(ifd < 0)) { - fprintf(stderr, "Error: Could not initialize Inotify (%s)\n", strerror(errno)); + fprintf(stderr, "Error: Could not initialize inotify (%s)\n", strerror(errno)); exit(EXIT_FAILURE); } @@ -403,8 +414,13 @@ static int watch_files(struct file_struct *files, int n_files) len = read(ifd, buf, (n_files * INOTIFY_BUFLEN)); if (unlikely(len < 0)) { - fprintf(stderr, "Error: Could not read inotify events (%s)\n", strerror(errno)); - exit(EXIT_FAILURE); + /* Some form of signal, likely ^Z/fg's STOP and CONT interrupted the inotify read, retry */ + if (errno == EINTR || errno == EAGAIN) + continue; /* Keep trying */ + else { + fprintf(stderr, "Error: Could not read inotify events (%s)\n", strerror(errno)); + exit(EXIT_FAILURE); + } } while (ev_idx < len) { @@ -415,7 +431,9 @@ static int watch_files(struct file_struct *files, int n_files) /* Which file has produced the event? */ for (i = 0; i < n_files; i++) { - if (!files[i].ignore && files[i].fd >= 0 && files[i].i_watch == inev->wd) { + if (!files[i].ignore + && files[i].fd >= 0 + && files[i].i_watch == inev->wd) { f = &files[i]; break; } @@ -432,7 +450,6 @@ static int watch_files(struct file_struct *files, int n_files) } close(ifd); - return -1; } @@ -457,7 +474,7 @@ int main(int argc, char **argv) } else if (*optarg == '-') optarg++; - if (!isdigit(*optarg)) { + if (!is_digit(*optarg)) { fprintf(stderr, "Invalid number of lines: %s\n", optarg); exit(EXIT_FAILURE); } @@ -32,6 +32,8 @@ struct file_struct { #define IS_TAILABLE(mode) \ (S_ISREG(mode) || IS_PIPELIKE(mode) || S_ISCHR(mode)) +#define is_digit(c) ((c) >= '0' && (c) <= '9') + #ifdef DEBUG # define dprintf(fmt, args...) fprintf(stderr, fmt, ##args) #else |