diff options
Diffstat (limited to 'lib/readline/histfile.c')
| -rw-r--r-- | lib/readline/histfile.c | 833 |
1 files changed, 833 insertions, 0 deletions
diff --git a/lib/readline/histfile.c b/lib/readline/histfile.c new file mode 100644 index 0000000..3bfec55 --- /dev/null +++ b/lib/readline/histfile.c @@ -0,0 +1,833 @@ +/* histfile.c - functions to manipulate the history file. */ + +/* Copyright (C) 1989-2019 Free Software Foundation, Inc. + + This file contains the GNU History Library (History), a set of + routines for managing the text of previously typed lines. + + History is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + History is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with History. If not, see <http://www.gnu.org/licenses/>. +*/ + +/* The goal is to make the implementation transparent, so that you + don't have to know what data types are used, just what functions + you can call. I think I have done that. */ + +#define READLINE_LIBRARY + +#if defined (__TANDEM) +# define _XOPEN_SOURCE_EXTENDED 1 +# include <unistd.h> +# include <floss.h> +#endif + +#if defined (HAVE_CONFIG_H) +# include <config.h> +#endif + +#include <stdio.h> + +#if defined (HAVE_LIMITS_H) +# include <limits.h> +#endif + +#include <sys/types.h> +#if ! defined (_MINIX) && defined (HAVE_SYS_FILE_H) +# include <sys/file.h> +#endif +#include "posixstat.h" +#include <fcntl.h> + +#if defined (HAVE_STDLIB_H) +# include <stdlib.h> +#else +# include "ansi_stdlib.h" +#endif /* HAVE_STDLIB_H */ + +#if defined (HAVE_UNISTD_H) +# include <unistd.h> +#endif + +#include <ctype.h> + +#if defined (__EMX__) +# undef HAVE_MMAP +#endif + +#ifdef HISTORY_USE_MMAP +# include <sys/mman.h> + +# ifdef MAP_FILE +# define MAP_RFLAGS (MAP_FILE|MAP_PRIVATE) +# define MAP_WFLAGS (MAP_FILE|MAP_SHARED) +# else +# define MAP_RFLAGS MAP_PRIVATE +# define MAP_WFLAGS MAP_SHARED +# endif + +# ifndef MAP_FAILED +# define MAP_FAILED ((void *)-1) +# endif + +#endif /* HISTORY_USE_MMAP */ + +#if defined(_WIN32) +# define WIN32_LEAN_AND_MEAN +# include <windows.h> +#endif + +/* If we're compiling for __EMX__ (OS/2) or __CYGWIN__ (cygwin32 environment + on win 95/98/nt), we want to open files with O_BINARY mode so that there + is no \n -> \r\n conversion performed. On other systems, we don't want to + mess around with O_BINARY at all, so we ensure that it's defined to 0. */ +#if defined (__EMX__) || defined (__CYGWIN__) +# ifndef O_BINARY +# define O_BINARY 0 +# endif +#else /* !__EMX__ && !__CYGWIN__ */ +# undef O_BINARY +# define O_BINARY 0 +#endif /* !__EMX__ && !__CYGWIN__ */ + +#include <errno.h> +#if !defined (errno) +extern int errno; +#endif /* !errno */ + +#include "history.h" +#include "histlib.h" + +#include "rlshell.h" +#include "xmalloc.h" + +#if !defined (PATH_MAX) +# define PATH_MAX 1024 /* default */ +#endif + +/* history file version; currently unused */ +int history_file_version = 1; + +/* If non-zero, we write timestamps to the history file in history_do_write() */ +int history_write_timestamps = 0; + +/* If non-zero, we assume that a history file that starts with a timestamp + uses timestamp-delimited entries and can include multi-line history + entries. Used by read_history_range */ +int history_multiline_entries = 0; + +/* Immediately after a call to read_history() or read_history_range(), this + will return the number of lines just read from the history file in that + call. */ +int history_lines_read_from_file = 0; + +/* Immediately after a call to write_history() or history_do_write(), this + will return the number of lines just written to the history file in that + call. This also works with history_truncate_file. */ +int history_lines_written_to_file = 0; + +/* Does S look like the beginning of a history timestamp entry? Placeholder + for more extensive tests. */ +#define HIST_TIMESTAMP_START(s) (*(s) == history_comment_char && isdigit ((unsigned char)(s)[1]) ) + +static char *history_backupfile (const char *); +static char *history_tempfile (const char *); +static int histfile_backup (const char *, const char *); +static int histfile_restore (const char *, const char *); +static int history_rename (const char *, const char *); + +/* Return the string that should be used in the place of this + filename. This only matters when you don't specify the + filename to read_history (), or write_history (). */ +static char * +history_filename (const char *filename) +{ + char *return_val; + const char *home; + int home_len; + + return_val = filename ? savestring (filename) : (char *)NULL; + + if (return_val) + return (return_val); + + home = sh_get_env_value ("HOME"); +#if defined (_WIN32) + if (home == 0) + home = sh_get_env_value ("APPDATA"); +#endif + + if (home == 0) + return (NULL); + else + home_len = strlen (home); + + return_val = (char *)xmalloc (2 + home_len + 8); /* strlen(".history") == 8 */ + strcpy (return_val, home); + return_val[home_len] = '/'; +#if defined (__MSDOS__) + strcpy (return_val + home_len + 1, "_history"); +#else + strcpy (return_val + home_len + 1, ".history"); +#endif + + return (return_val); +} + +static char * +history_backupfile (const char *filename) +{ + const char *fn; + char *ret, linkbuf[PATH_MAX+1]; + size_t len; + ssize_t n; + struct stat fs; + + fn = filename; +#if defined (HAVE_READLINK) + /* Follow symlink to avoid backing up symlink itself; call will fail if + not a symlink */ + if ((n = readlink (filename, linkbuf, sizeof (linkbuf) - 1)) > 0) + { + linkbuf[n] = '\0'; + fn = linkbuf; + } +#endif + + len = strlen (fn); + ret = xmalloc (len + 2); + strcpy (ret, fn); + ret[len] = '-'; + ret[len+1] = '\0'; + return ret; +} + +static char * +history_tempfile (const char *filename) +{ + const char *fn; + char *ret, linkbuf[PATH_MAX+1]; + size_t len; + ssize_t n; + struct stat fs; + int pid; + + fn = filename; +#if defined (HAVE_READLINK) + /* Follow symlink so tempfile created in the same directory as any symlinked + history file; call will fail if not a symlink */ + if ((n = readlink (filename, linkbuf, sizeof (linkbuf) - 1)) > 0) + { + linkbuf[n] = '\0'; + fn = linkbuf; + } +#endif + + len = strlen (fn); + ret = xmalloc (len + 11); + strcpy (ret, fn); + + pid = (int)getpid (); + + /* filename-PID.tmp */ + ret[len] = '-'; + ret[len+1] = (pid / 10000 % 10) + '0'; + ret[len+2] = (pid / 1000 % 10) + '0'; + ret[len+3] = (pid / 100 % 10) + '0'; + ret[len+4] = (pid / 10 % 10) + '0'; + ret[len+5] = (pid % 10) + '0'; + strcpy (ret + len + 6, ".tmp"); + + return ret; +} + +/* Add the contents of FILENAME to the history list, a line at a time. + If FILENAME is NULL, then read from ~/.history. Returns 0 if + successful, or errno if not. */ +int +read_history (const char *filename) +{ + return (read_history_range (filename, 0, -1)); +} + +/* Read a range of lines from FILENAME, adding them to the history list. + Start reading at the FROM'th line and end at the TO'th. If FROM + is zero, start at the beginning. If TO is less than FROM, read + until the end of the file. If FILENAME is NULL, then read from + ~/.history. Returns 0 if successful, or errno if not. */ +int +read_history_range (const char *filename, int from, int to) +{ + register char *line_start, *line_end, *p; + char *input, *buffer, *bufend, *last_ts; + int file, current_line, chars_read, has_timestamps, reset_comment_char; + struct stat finfo; + size_t file_size; +#if defined (EFBIG) + int overflow_errno = EFBIG; +#elif defined (EOVERFLOW) + int overflow_errno = EOVERFLOW; +#else + int overflow_errno = EIO; +#endif + + history_lines_read_from_file = 0; + + buffer = last_ts = (char *)NULL; + input = history_filename (filename); + file = input ? open (input, O_RDONLY|O_BINARY, 0666) : -1; + + if ((file < 0) || (fstat (file, &finfo) == -1)) + goto error_and_exit; + + if (S_ISREG (finfo.st_mode) == 0) + { +#ifdef EFTYPE + errno = EFTYPE; +#else + errno = EINVAL; +#endif + goto error_and_exit; + } + + file_size = (size_t)finfo.st_size; + + /* check for overflow on very large files */ + if (file_size != finfo.st_size || file_size + 1 < file_size) + { + errno = overflow_errno; + goto error_and_exit; + } + + if (file_size == 0) + { + xfree (input); + close (file); + return 0; /* don't waste time if we don't have to */ + } + +#ifdef HISTORY_USE_MMAP + /* We map read/write and private so we can change newlines to NULs without + affecting the underlying object. */ + buffer = (char *)mmap (0, file_size, PROT_READ|PROT_WRITE, MAP_RFLAGS, file, 0); + if ((void *)buffer == MAP_FAILED) + { + errno = overflow_errno; + goto error_and_exit; + } + chars_read = file_size; +#else + buffer = (char *)malloc (file_size + 1); + if (buffer == 0) + { + errno = overflow_errno; + goto error_and_exit; + } + + chars_read = read (file, buffer, file_size); +#endif + if (chars_read < 0) + { + error_and_exit: + if (errno != 0) + chars_read = errno; + else + chars_read = EIO; + if (file >= 0) + close (file); + + FREE (input); +#ifndef HISTORY_USE_MMAP + FREE (buffer); +#endif + + return (chars_read); + } + + close (file); + + /* Set TO to larger than end of file if negative. */ + if (to < 0) + to = chars_read; + + /* Start at beginning of file, work to end. */ + bufend = buffer + chars_read; + *bufend = '\0'; /* null-terminate buffer for timestamp checks */ + current_line = 0; + + /* Heuristic: the history comment character rarely changes, so assume we + have timestamps if the buffer starts with `#[:digit:]' and temporarily + set history_comment_char so timestamp parsing works right */ + reset_comment_char = 0; + if (history_comment_char == '\0' && buffer[0] == '#' && isdigit ((unsigned char)buffer[1])) + { + history_comment_char = '#'; + reset_comment_char = 1; + } + + has_timestamps = HIST_TIMESTAMP_START (buffer); + history_multiline_entries += has_timestamps && history_write_timestamps; + + /* Skip lines until we are at FROM. */ + if (has_timestamps) + last_ts = buffer; + for (line_start = line_end = buffer; line_end < bufend && current_line < from; line_end++) + if (*line_end == '\n') + { + p = line_end + 1; + /* If we see something we think is a timestamp, continue with this + line. We should check more extensively here... */ + if (HIST_TIMESTAMP_START(p) == 0) + current_line++; + else + last_ts = p; + line_start = p; + /* If we are at the last line (current_line == from) but we have + timestamps (has_timestamps), then line_start points to the + text of the last command, and we need to skip to its end. */ + if (current_line >= from && has_timestamps) + { + for (line_end = p; line_end < bufend && *line_end != '\n'; line_end++) + ; + line_start = (*line_end == '\n') ? line_end + 1 : line_end; + } + } + + /* If there are lines left to gobble, then gobble them now. */ + for (line_end = line_start; line_end < bufend; line_end++) + if (*line_end == '\n') + { + /* Change to allow Windows-like \r\n end of line delimiter. */ + if (line_end > line_start && line_end[-1] == '\r') + line_end[-1] = '\0'; + else + *line_end = '\0'; + + if (*line_start) + { + if (HIST_TIMESTAMP_START(line_start) == 0) + { + if (last_ts == NULL && history_length > 0 && history_multiline_entries) + _hs_append_history_line (history_length - 1, line_start); + else + add_history (line_start); + if (last_ts) + { + add_history_time (last_ts); + last_ts = NULL; + } + } + else + { + last_ts = line_start; + current_line--; + } + } + + current_line++; + + if (current_line >= to) + break; + + line_start = line_end + 1; + } + + history_lines_read_from_file = current_line; + if (reset_comment_char) + history_comment_char = '\0'; + + FREE (input); +#ifndef HISTORY_USE_MMAP + FREE (buffer); +#else + munmap (buffer, file_size); +#endif + + return (0); +} + +/* We need a special version for WIN32 because Windows rename() refuses to + overwrite an existing file. */ +static int +history_rename (const char *old, const char *new) +{ +#if defined (_WIN32) + return (MoveFileEx (old, new, MOVEFILE_REPLACE_EXISTING) == 0 ? -1 : 0); +#else + return (rename (old, new)); +#endif +} + +/* Save FILENAME to BACK, handling case where FILENAME is a symlink + (e.g., ~/.bash_history -> .histfiles/.bash_history.$HOSTNAME) */ +static int +histfile_backup (const char *filename, const char *back) +{ +#if defined (HAVE_READLINK) + char linkbuf[PATH_MAX+1]; + ssize_t n; + + /* Follow to target of symlink to avoid renaming symlink itself */ + if ((n = readlink (filename, linkbuf, sizeof (linkbuf) - 1)) > 0) + { + linkbuf[n] = '\0'; + return (history_rename (linkbuf, back)); + } +#endif + return (history_rename (filename, back)); +} + +/* Restore ORIG from BACKUP handling case where ORIG is a symlink + (e.g., ~/.bash_history -> .histfiles/.bash_history.$HOSTNAME) */ +static int +histfile_restore (const char *backup, const char *orig) +{ +#if defined (HAVE_READLINK) + char linkbuf[PATH_MAX+1]; + ssize_t n; + + /* Follow to target of symlink to avoid renaming symlink itself */ + if ((n = readlink (orig, linkbuf, sizeof (linkbuf) - 1)) > 0) + { + linkbuf[n] = '\0'; + return (history_rename (backup, linkbuf)); + } +#endif + return (history_rename (backup, orig)); +} + +/* Should we call chown, based on whether finfo and nfinfo describe different + files with different owners? */ + +#define SHOULD_CHOWN(finfo, nfinfo) \ + (finfo.st_uid != nfinfo.st_uid || finfo.st_gid != nfinfo.st_gid) + +/* Truncate the history file FNAME, leaving only LINES trailing lines. + If FNAME is NULL, then use ~/.history. Writes a new file and renames + it to the original name. Returns 0 on success, errno on failure. */ +int +history_truncate_file (const char *fname, int lines) +{ + char *buffer, *filename, *tempname, *bp, *bp1; /* bp1 == bp+1 */ + int file, chars_read, rv, orig_lines, exists, r; + struct stat finfo, nfinfo; + size_t file_size; + + history_lines_written_to_file = 0; + + buffer = (char *)NULL; + filename = history_filename (fname); + tempname = 0; + file = filename ? open (filename, O_RDONLY|O_BINARY, 0666) : -1; + rv = exists = 0; + + /* Don't try to truncate non-regular files. */ + if (file == -1 || fstat (file, &finfo) == -1) + { + rv = errno; + if (file != -1) + close (file); + goto truncate_exit; + } + exists = 1; + + nfinfo.st_uid = finfo.st_uid; + nfinfo.st_gid = finfo.st_gid; + + if (S_ISREG (finfo.st_mode) == 0) + { + close (file); +#ifdef EFTYPE + rv = EFTYPE; +#else + rv = EINVAL; +#endif + goto truncate_exit; + } + + file_size = (size_t)finfo.st_size; + + /* check for overflow on very large files */ + if (file_size != finfo.st_size || file_size + 1 < file_size) + { + close (file); +#if defined (EFBIG) + rv = errno = EFBIG; +#elif defined (EOVERFLOW) + rv = errno = EOVERFLOW; +#else + rv = errno = EINVAL; +#endif + goto truncate_exit; + } + + buffer = (char *)malloc (file_size + 1); + if (buffer == 0) + { + rv = errno; + close (file); + goto truncate_exit; + } + + chars_read = read (file, buffer, file_size); + close (file); + + if (chars_read <= 0) + { + rv = (chars_read < 0) ? errno : 0; + goto truncate_exit; + } + + orig_lines = lines; + /* Count backwards from the end of buffer until we have passed + LINES lines. bp1 is set funny initially. But since bp[1] can't + be a comment character (since it's off the end) and *bp can't be + both a newline and the history comment character, it should be OK. */ + for (bp1 = bp = buffer + chars_read - 1; lines && bp > buffer; bp--) + { + if (*bp == '\n' && HIST_TIMESTAMP_START(bp1) == 0) + lines--; + bp1 = bp; + } + + /* If this is the first line, then the file contains exactly the + number of lines we want to truncate to, so we don't need to do + anything. It's the first line if we don't find a newline between + the current value of i and 0. Otherwise, write from the start of + this line until the end of the buffer. */ + for ( ; bp > buffer; bp--) + { + if (*bp == '\n' && HIST_TIMESTAMP_START(bp1) == 0) + { + bp++; + break; + } + bp1 = bp; + } + + /* Write only if there are more lines in the file than we want to + truncate to. */ + if (bp <= buffer) + { + rv = 0; + /* No-op if LINES == 0 at this point */ + history_lines_written_to_file = orig_lines - lines; + goto truncate_exit; + } + + tempname = history_tempfile (filename); + + if ((file = open (tempname, O_WRONLY|O_CREAT|O_TRUNC|O_BINARY, 0600)) != -1) + { + if (write (file, bp, chars_read - (bp - buffer)) < 0) + rv = errno; + + if (fstat (file, &nfinfo) < 0 && rv == 0) + rv = errno; + + if (close (file) < 0 && rv == 0) + rv = errno; + } + else + rv = errno; + + truncate_exit: + FREE (buffer); + + history_lines_written_to_file = orig_lines - lines; + + if (rv == 0 && filename && tempname) + rv = histfile_restore (tempname, filename); + + if (rv != 0) + { + rv = errno; + if (tempname) + unlink (tempname); + history_lines_written_to_file = 0; + } + +#if defined (HAVE_CHOWN) + /* Make sure the new filename is owned by the same user as the old. If one + user is running this, it's a no-op. If the shell is running after sudo + with a shared history file, we don't want to leave the history file + owned by root. */ + if (rv == 0 && exists && SHOULD_CHOWN (finfo, nfinfo)) + r = chown (filename, finfo.st_uid, finfo.st_gid); +#endif + + xfree (filename); + FREE (tempname); + + return rv; +} + +/* Workhorse function for writing history. Writes the last NELEMENT entries + from the history list to FILENAME. OVERWRITE is non-zero if you + wish to replace FILENAME with the entries. */ +static int +history_do_write (const char *filename, int nelements, int overwrite) +{ + register int i; + char *output, *tempname, *histname; + int file, mode, rv, exists; + struct stat finfo, nfinfo; +#ifdef HISTORY_USE_MMAP + size_t cursize; + + history_lines_written_to_file = 0; + + mode = overwrite ? O_RDWR|O_CREAT|O_TRUNC|O_BINARY : O_RDWR|O_APPEND|O_BINARY; +#else + mode = overwrite ? O_WRONLY|O_CREAT|O_TRUNC|O_BINARY : O_WRONLY|O_APPEND|O_BINARY; +#endif + histname = history_filename (filename); + exists = histname ? (stat (histname, &finfo) == 0) : 0; + + tempname = (overwrite && exists && S_ISREG (finfo.st_mode)) ? history_tempfile (histname) : 0; + output = tempname ? tempname : histname; + + file = output ? open (output, mode, 0600) : -1; + rv = 0; + + if (file == -1) + { + rv = errno; + FREE (histname); + FREE (tempname); + return (rv); + } + +#ifdef HISTORY_USE_MMAP + cursize = overwrite ? 0 : lseek (file, 0, SEEK_END); +#endif + + if (nelements > history_length) + nelements = history_length; + + /* Build a buffer of all the lines to write, and write them in one syscall. + Suggested by Peter Ho (peter@robosts.oxford.ac.uk). */ + { + HIST_ENTRY **the_history; /* local */ + register int j; + int buffer_size; + char *buffer; + + the_history = history_list (); + /* Calculate the total number of bytes to write. */ + for (buffer_size = 0, i = history_length - nelements; i < history_length; i++) + { + if (history_write_timestamps && the_history[i]->timestamp && the_history[i]->timestamp[0]) + buffer_size += strlen (the_history[i]->timestamp) + 1; + buffer_size += strlen (the_history[i]->line) + 1; + } + + /* Allocate the buffer, and fill it. */ +#ifdef HISTORY_USE_MMAP + if (ftruncate (file, buffer_size+cursize) == -1) + goto mmap_error; + buffer = (char *)mmap (0, buffer_size, PROT_READ|PROT_WRITE, MAP_WFLAGS, file, cursize); + if ((void *)buffer == MAP_FAILED) + { +mmap_error: + rv = errno; + close (file); + if (tempname) + unlink (tempname); + FREE (histname); + FREE (tempname); + return rv; + } +#else + buffer = (char *)malloc (buffer_size); + if (buffer == 0) + { + rv = errno; + close (file); + if (tempname) + unlink (tempname); + FREE (histname); + FREE (tempname); + return rv; + } +#endif + + for (j = 0, i = history_length - nelements; i < history_length; i++) + { + if (history_write_timestamps && the_history[i]->timestamp && the_history[i]->timestamp[0]) + { + strcpy (buffer + j, the_history[i]->timestamp); + j += strlen (the_history[i]->timestamp); + buffer[j++] = '\n'; + } + strcpy (buffer + j, the_history[i]->line); + j += strlen (the_history[i]->line); + buffer[j++] = '\n'; + } + +#ifdef HISTORY_USE_MMAP + if (msync (buffer, buffer_size, MS_ASYNC) != 0 || munmap (buffer, buffer_size) != 0) + rv = errno; +#else + if (write (file, buffer, buffer_size) < 0) + rv = errno; + xfree (buffer); +#endif + } + + history_lines_written_to_file = nelements; + + if (close (file) < 0 && rv == 0) + rv = errno; + + if (rv == 0 && histname && tempname) + rv = histfile_restore (tempname, histname); + + if (rv != 0) + { + rv = errno; + if (tempname) + unlink (tempname); + history_lines_written_to_file = 0; + } + +#if defined (HAVE_CHOWN) + /* Make sure the new filename is owned by the same user as the old. If one + user is running this, it's a no-op. If the shell is running after sudo + with a shared history file, we don't want to leave the history file + owned by root. */ + if (rv == 0 && exists) + mode = chown (histname, finfo.st_uid, finfo.st_gid); +#endif + + FREE (histname); + FREE (tempname); + + return (rv); +} + +/* Append NELEMENT entries to FILENAME. The entries appended are from + the end of the list minus NELEMENTs up to the end of the list. */ +int +append_history (int nelements, const char *filename) +{ + return (history_do_write (filename, nelements, HISTORY_APPEND)); +} + +/* Overwrite FILENAME with the current history. If FILENAME is NULL, + then write the history list to ~/.history. Values returned + are as in read_history ().*/ +int +write_history (const char *filename) +{ + return (history_do_write (filename, history_length, HISTORY_OVERWRITE)); +} |