diff options
| -rw-r--r-- | miscutils/less.c | 47 |
1 files changed, 28 insertions, 19 deletions
diff --git a/miscutils/less.c b/miscutils/less.c index b38fcf7..be8d20e 100644 --- a/miscutils/less.c +++ b/miscutils/less.c @@ -165,12 +165,6 @@ enum { enum { pattern_valid = 0 }; #endif -enum { - READING_FILE = -1, - READING_STDIN = -2, - READING_NONREG = -3 -}; - struct globals { int cur_fline; /* signed */ int kbd_fd; /* fd to get input from */ @@ -195,7 +189,10 @@ struct globals { char *filename; char **files; #if ENABLE_FEATURE_LESS_FLAGS - int num_lines; /* input source if < 0, line count if >= 0 */ + int num_lines; /* a flag if < 0, line count if >= 0 */ +# define REOPEN_AND_COUNT (-1) +# define REOPEN_STDIN (-2) +# define NOT_REGULAR_FILE (-3) #endif #if ENABLE_FEATURE_LESS_MARKS unsigned num_marks; @@ -622,14 +619,29 @@ static void update_num_lines(void) char buf[4096]; /* only do this for regular files */ - if (num_lines == READING_FILE) { + if (num_lines != NOT_REGULAR_FILE) { count = 0; - fd = open(filename, O_RDONLY); + fd = open("/proc/self/fd/0", O_RDONLY); + if (fd < 0 && num_lines == REOPEN_AND_COUNT) { + /* "filename" is valid only if REOPEN_AND_COUNT */ + fd = open(filename, O_RDONLY); + } if (fd < 0) { /* somebody stole my file! */ - num_lines = READING_NONREG; + num_lines = NOT_REGULAR_FILE; return; } +#if ENABLE_FEATURE_LESS_FLAGS + { + struct stat stbuf; + if (fstat(fd, &stbuf) != 0 + || !S_ISREG(stbuf.st_mode) + ) { + num_lines = NOT_REGULAR_FILE; + goto do_close; + } + } +#endif while ((len = safe_read(fd, buf, sizeof(buf))) > 0) { for (i = 0; i < len; ++i) { if (buf[i] == '\n' && ++count == MAXLINES) @@ -638,6 +650,7 @@ static void update_num_lines(void) } done: num_lines = count; + do_close: close(fd); } } @@ -991,18 +1004,17 @@ static void buffer_lineno(int lineno) static void open_file_and_read_lines(void) { if (filename) { + xmove_fd(xopen(filename, O_RDONLY), STDIN_FILENO); #if ENABLE_FEATURE_LESS_FLAGS - struct stat stbuf; - - xstat(filename, &stbuf); - if (!S_ISREG(stbuf.st_mode)) - num_lines = READING_NONREG; + num_lines = REOPEN_AND_COUNT; #endif - xmove_fd(xopen(filename, O_RDONLY), STDIN_FILENO); } else { /* "less" with no arguments in argv[] */ /* For status line only */ filename = xstrdup(bb_msg_standard_input); +#if ENABLE_FEATURE_LESS_FLAGS + num_lines = REOPEN_STDIN; +#endif } readpos = 0; readeof = 0; @@ -1026,9 +1038,6 @@ static void reinitialize(void) max_fline = -1; cur_fline = 0; max_lineno = 0; -#if ENABLE_FEATURE_LESS_FLAGS - num_lines = filename ? READING_FILE : READING_STDIN; -#endif open_file_and_read_lines(); #if ENABLE_FEATURE_LESS_ASK_TERMINAL if (G.winsize_err) |