Sorry about all the iterations. Hopefully this version is complete. cheers, Pádraig.
>From 55d1c2e2ea14f0713d7604323b4f43a83237897b Mon Sep 17 00:00:00 2001 From: =?utf-8?q?P=C3=A1draig=20Brady?= <p...@draigbrady.com> Date: Tue, 24 Mar 2009 14:29:21 +0000 Subject: [PATCH] ls: Fix alignment when month names have varying widths MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit
Reported by Samuel Thibault and Stéphane Raimbault, as the glibc fr_FR locale has recently changed to use the official but variable width abbreviated month names. Other glibc locales also have variable widths. http://sourceware.org/ml/libc-locales/2008-q1/msg00035.html http://sourceware.org/bugzilla/show_bug.cgi?id=9859 * NEWS: Mention the fix * gl/lib/mbsalign.c: A new module to align and truncate a string in a specified number of screen cells, while handling multi-byte characters appropriately. * gl/lib/mbsalign.h: Ditto * gl/modules/mbsalign: Ditto * bootstrap.conf: Reference the new module * src/ls.c (abmon_init): New function, precompute the abbreviated months aligned left in a minimum width column <= 5 screen cells. (align_nstrftime): New function, replace the first %b in the format specification to strftime with the precomputed month string. Note using the cached month strings speeds up `ls -lU` by around 17% on glibc-2.7-2 on linux at least. Also if we implement this function using heap storage rather than automatic storage, and use snprintf instead of strcpy, ls will slow down by 2% and 1% respectively (i.e. a net gain of 14% rather than 17%). --- NEWS | 3 + bootstrap.conf | 1 + gl/lib/mbsalign.c | 188 +++++++++++++++++++++++++++++++++++++++++++++++++++ gl/lib/mbsalign.h | 23 ++++++ gl/modules/mbsalign | 25 +++++++ src/ls.c | 104 +++++++++++++++++++++++++++- 6 files changed, 341 insertions(+), 3 deletions(-) create mode 100644 gl/lib/mbsalign.c create mode 100644 gl/lib/mbsalign.h create mode 100644 gl/modules/mbsalign diff --git a/NEWS b/NEWS index 3ef5f94..6538071 100644 --- a/NEWS +++ b/NEWS @@ -28,6 +28,9 @@ GNU coreutils NEWS -*- outline -*- ls --sort=version (-v) sorted names beginning with "." inconsistently. Now, names that start with "." are always listed before those that don't. + ls now aligns output correctly in the presence of abbreviated month names + from the locale database that have differing widths. + pr: fix the bug whereby --indent=N (-o) did not indent header lines [bug introduced in coreutils-6.9.90] diff --git a/bootstrap.conf b/bootstrap.conf index 0747bb8..ae033d9 100644 --- a/bootstrap.conf +++ b/bootstrap.conf @@ -70,6 +70,7 @@ gnulib_modules=" long-options lstat malloc manywarnings mbrtowc + mbsalign mbswidth memcasecmp memcmp2 mempcpy memrchr mgetgroups diff --git a/gl/lib/mbsalign.c b/gl/lib/mbsalign.c new file mode 100644 index 0000000..1079a71 --- /dev/null +++ b/gl/lib/mbsalign.c @@ -0,0 +1,188 @@ +/* Align/Truncate a string in a given screen width + Copyright (C) 2009 Free Software Foundation, Inc. + + This program 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. + + This program 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 this program. If not, see <http://www.gnu.org/licenses/>. */ + +/* Written by Pádraig Brady. */ + +#include <config.h> +#include "mbsalign.h" + +#include <stdlib.h> +#include <string.h> +#include <stdio.h> +#include <stdbool.h> +#include <wchar.h> +#include <wctype.h> + +/* Replace non printable chars. + Return 1 if replacement made, 0 otherwise. */ + +static bool +wc_ensure_printable (wchar_t *wchars) +{ + bool replaced = false; + wchar_t *wc = wchars; + while (*wc) + { + if (!iswprint ((wint_t) *wc)) + { + *wc = 0xFFFD; /* L'\uFFFD' (replacement char) */ + replaced = true; + } + wc++; + } + return replaced; +} + +/* Truncate wchar string to width cells. + * Returns number of cells used. */ + +static size_t +wc_truncate (wchar_t *wc, size_t width) +{ + size_t cells = 0; + int next_cells = 0; + + while (*wc) + { + next_cells = wcwidth (*wc); + if (next_cells == -1) /* non printable */ + { + *wc = 0xFFFD; /* L'\uFFFD' (replacement char) */ + next_cells = 1; + } + if (cells + next_cells > width) + break; + cells += next_cells; + wc++; + } + *wc = L'\0'; + return cells; +} + +/* FIXME: move this function to gnulib as it's missing on: + OpenBSD 3.8, IRIX 5.3, Solaris 2.5.1, mingw, BeOS */ + +static int +rpl_wcswidth (const wchar_t *s, size_t n) +{ + int ret = 0; + + while (n-- > 0 && *s != L'\0') + { + int nwidth = wcwidth (*s++); + if (nwidth == -1) /* non printable */ + return -1; + ret += nwidth; + } + + return ret; +} + +/* Align a string in a given screen width, handling multi-byte characters. + In addition if the string is too large for the width, truncate it to fit. + When centering, the number of trailing spaces may be 1 less than the + number of leading spaces. + Return the number of bytes written to or required in dest (without + the trailing NUL). A value >= dest_size means there wasn't enough space. + If an error is encountered, a negative value is returned. + The width parameter both specifies the width to align/pad/truncate to, + and is updated to return the width used before padding. */ + +int +mbsalign (const char *src, char *dest, size_t dest_size, + size_t *width, mbs_align_t align) +{ + int ret = -1; + size_t src_size = strlen (src) + 1; + char *newstr = NULL; + wchar_t *str_wc = NULL; + const char *str_to_print = src; + size_t n_used = src_size - 1; + size_t n_spaces = 0; + bool conversion = false; + bool wc_enabled = false; + + if (MB_CUR_MAX > 1) + { + size_t src_chars = mbstowcs (NULL, src, 0); + if (src_chars == (size_t) -1) + goto mbsalign_cleanup; + src_chars += 1; /* make space for NUL */ + str_wc = malloc (src_chars * sizeof (wchar_t)); + if (str_wc == NULL) + goto mbsalign_cleanup; + if (mbstowcs (str_wc, src, src_chars) > 0) + { + str_wc[src_chars - 1] = L'\0'; + wc_enabled = true; + conversion = wc_ensure_printable (str_wc); + n_used = rpl_wcswidth (str_wc, src_chars); + } + } + + if (conversion || (n_used > *width)) + { + newstr = malloc (src_size); + if (newstr == NULL) + goto mbsalign_cleanup; + str_to_print = newstr; + if (wc_enabled) + { + n_used = wc_truncate (str_wc, *width); + wcstombs (newstr, str_wc, src_size); + } + else + { + n_used = *width; + memcpy (newstr, src, *width); + newstr[*width] = '\0'; + } + } + + if (*width > n_used) + n_spaces = *width - n_used; + *width = n_used; /* indicate to caller how many cells needed. */ + + /* FIXME: Should I be padding with "figure space" (\u2007) + rather than spaces below? (only if non ascii data present). */ + switch (align) + { + case MBS_ALIGN_CENTER: + ret = snprintf (dest, dest_size, "%*s%s%*s", + n_spaces / 2 + n_spaces % 2, "", + str_to_print, n_spaces / 2, ""); + break; + case MBS_ALIGN_LEFT: + ret = snprintf (dest, dest_size, "%s%*s", str_to_print, n_spaces, ""); + break; + case MBS_ALIGN_RIGHT: + ret = snprintf (dest, dest_size, "%*s%s", n_spaces, "", str_to_print); + break; + } + +mbsalign_cleanup: + + free (str_wc); + free (newstr); + + return ret; +} + +/* + * Local variables: + * indent-tabs-mode: nil + * End: + */ diff --git a/gl/lib/mbsalign.h b/gl/lib/mbsalign.h new file mode 100644 index 0000000..69e3966 --- /dev/null +++ b/gl/lib/mbsalign.h @@ -0,0 +1,23 @@ +/* Align/Truncate a string in a given screen width + Copyright (C) 2009 Free Software Foundation, Inc. + + This program 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. + + This program 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 this program. If not, see <http://www.gnu.org/licenses/>. */ + +#include <stddef.h> + +typedef enum { MBS_ALIGN_LEFT, MBS_ALIGN_RIGHT, MBS_ALIGN_CENTER } mbs_align_t; + +int +mbsalign (const char *src, char *dest, size_t dest_size, + size_t *width, mbs_align_t align); diff --git a/gl/modules/mbsalign b/gl/modules/mbsalign new file mode 100644 index 0000000..f5845dc --- /dev/null +++ b/gl/modules/mbsalign @@ -0,0 +1,25 @@ +Description: +Align/Truncate a string in a given screen width. + +Files: +lib/mbsalign.c +lib/mbsalign.h + +Depends-on: +wchar +wctype +wcwidth + +configure.ac: + +Makefile.am: +lib_SOURCES += mbsalign.c mbsalign.h + +Include: +"mbsalign.h" + +License: +LGPL + +Maintainer: +Pádraig Brady diff --git a/src/ls.c b/src/ls.c index d30e5a0..c55f525 100644 --- a/src/ls.c +++ b/src/ls.c @@ -67,6 +67,10 @@ #include <selinux/selinux.h> #include <wchar.h> +#if HAVE_LANGINFO_CODESET +# include <langinfo.h> +#endif + /* Use SA_NOCLDSTOP as a proxy for whether the sigaction machinery is present. */ #ifndef SA_NOCLDSTOP @@ -105,6 +109,7 @@ #include "strftime.h" #include "xstrtol.h" #include "areadlink.h" +#include "mbsalign.h" #define PROGRAM_NAME (ls_mode == LS_LS ? "ls" \ : (ls_mode == LS_MULTI_COL \ @@ -695,6 +700,11 @@ static char const *long_time_format[2] = screen columns small, because many people work in windows with only 80 columns. But make this as wide as the other string below, for recent files. */ + /* TRANSLATORS: ls output needs to be aligned for ease of reading, + so be wary of using variable width fields from the locale. + Note %b is handled specially by ls and aligned correctly. + Note also that specifying a width as in %5b is erroneous as strftime + will count bytes rather than characters in multibyte locales. */ N_("%b %e %Y"), /* strftime format for recent files (younger than 6 months), in -l output. This should contain the month, day and time (at @@ -703,6 +713,11 @@ static char const *long_time_format[2] = screen columns small, because many people work in windows with only 80 columns. But make this as wide as the other string above, for non-recent files. */ + /* TRANSLATORS: ls output needs to be aligned for ease of reading, + so be wary of using variable width fields from the locale. + Note %b is handled specially by ls and aligned correctly. + Note also that specifying a width as in %5b is erroneous as strftime + will count bytes rather than characters in multibyte locales. */ N_("%b %e %H:%M") }; @@ -978,6 +993,56 @@ dired_dump_obstack (const char *prefix, struct obstack *os) } } +/* Read the abbreviated month names from the locale, to align them + and to determine the max width of the field and to truncate names + greater than our max allowed. + Note even though this handles multibyte locales correctly + it's not restricted to them as single byte locales can have + variable width abbreviated months and also precomputing/caching + the names was seen to increase the performance of ls significantly. */ + +/* max number of display cells to use */ +enum { MAX_MON_WIDTH = 5 }; +/* In the unlikely event that the abmon[] storage is not big enough + an error message will be displayed, and we revert to using + unmodified abbreviated month names from the locale database. */ +static char abmon[12][MAX_MON_WIDTH * 2 * MB_LEN_MAX + 1]; +/* minimum width needed to align %b, 0 => don't use precomputed values. */ +static size_t required_mon_width; + +static size_t +abmon_init (void) +{ +#ifdef HAVE_NL_LANGINFO + required_mon_width = MAX_MON_WIDTH; + size_t curr_max_width; + do + { + curr_max_width = required_mon_width; + required_mon_width = 0; + for (int i = 0; i < 12; i++) + { + size_t width = curr_max_width; + + int req = mbsalign (nl_langinfo (ABMON_1 + i), + abmon[i], sizeof (abmon[i]), + &width, MBS_ALIGN_LEFT); + + if (req == -1 || req >= sizeof(abmon[i])) + { + required_mon_width = 0; /* ignore precomputed strings. */ + return required_mon_width; + } + + required_mon_width = MAX (required_mon_width, width); + } + } + while (curr_max_width > required_mon_width); +#endif + + return required_mon_width; +} + static size_t dev_ino_hash (void const *x, size_t table_size) { @@ -1953,6 +2018,10 @@ decode_switches (int argc, char **argv) } } } + /* Note we leave %5b etc. alone so user widths/flags are honoured. */ + if (strstr(long_time_format[0],"%b") || strstr(long_time_format[1],"%b")) + if (!abmon_init()) + error (0, 0, _("error initializing month strings")); } return optind; @@ -3317,6 +3386,35 @@ print_current_files (void) } } +/* Replace the first %b with precomputed aligned month names. + Note on glibc-2.7 on linux at least this speeds up the whole `ls -lU` + process by around 17%, compared to letting strftime() handle the %b. */ + +static size_t +align_nstrftime (char *src, size_t size, char const *fmt, struct tm const *tm, + int __utc, int __ns) +{ + const char *nfmt = fmt; + /* In the unlikely event that rpl_fmt below is not large enough, + the replacement is not done. A malloc here slows ls down by 2% */ + char rpl_fmt[sizeof (abmon[0]) + 100]; + char *pb = NULL; + if (required_mon_width && (pb = strstr (fmt, "%b"))) + { + if (strlen(fmt) < (sizeof (rpl_fmt) - sizeof (abmon[0]) + 2)) + { + char *pfmt = rpl_fmt; + nfmt = rpl_fmt; + + pfmt = mempcpy (pfmt, fmt, pb - fmt); + pfmt = stpcpy (pfmt, abmon[tm->tm_mon]); + strcpy (pfmt, pb + 2); + } + } + size_t ret = nstrftime (src, size, nfmt, tm, __utc, __ns); + return ret; +} + /* Return the expected number of columns in a long-format time stamp, or zero if it cannot be calculated. */ @@ -3341,7 +3439,7 @@ long_time_expected_width (void) if (tm) { size_t len = - nstrftime (buf, sizeof buf, long_time_format[0], tm, 0, 0); + align_nstrftime (buf, sizeof buf, long_time_format[0], tm, 0, 0); if (len != 0) width = mbsnwidth (buf, len, 0); } @@ -3616,8 +3714,8 @@ print_long_format (const struct fileinfo *f) /* We assume here that all time zones are offset from UTC by a whole number of seconds. */ - s = nstrftime (p, TIME_STAMP_LEN_MAXIMUM + 1, fmt, - when_local, 0, when_timespec.tv_nsec); + s = align_nstrftime (p, TIME_STAMP_LEN_MAXIMUM + 1, fmt, + when_local, 0, when_timespec.tv_nsec); } if (s || !*p) -- 1.5.3.6
_______________________________________________ Bug-coreutils mailing list Bug-coreutils@gnu.org http://lists.gnu.org/mailman/listinfo/bug-coreutils
