X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fmodechange.c;h=8ac18799f8091534900d3ae25721ca8e42f2dba8;hb=7ef6c64e210ac0979d7e8ac69bc5b5208c2405ab;hp=a2697f67ff0243d0ee1a2335caa5aa10bef8334d;hpb=267a39bafd249d7eb9c37df06dc6defcf41cb343;p=gnulib.git
diff --git a/lib/modechange.c b/lib/modechange.c
index a2697f67f..8ac18799f 100644
--- a/lib/modechange.c
+++ b/lib/modechange.c
@@ -1,12 +1,12 @@
/* modechange.c -- file mode manipulation
- Copyright (C) 1989, 1990, 1997, 1998, 1999, 2001, 2003, 2004, 2005
- Free Software Foundation, Inc.
+ Copyright (C) 1989-1990, 1997-1999, 2001, 2003-2006, 2009-2014 Free Software
+ Foundation, Inc.
- This program is free software; you can redistribute it and/or modify
+ 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 2, or (at your option)
- any later version.
+ 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
@@ -14,21 +14,18 @@
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, write to the Free Software Foundation,
- Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+ along with this program. If not, see . */
/* Written by David MacKenzie */
-/* The ASCII mode string is compiled into an array of `struct
+/* The ASCII mode string is compiled into an array of 'struct
modechange', which can then be applied to each file to be changed.
We do this instead of re-parsing the ASCII string for each file
because the compiled form requires less computation to use; when
changing the mode of many files, this probably results in a
performance gain. */
-#if HAVE_CONFIG_H
-# include
-#endif
+#include
#include "modechange.h"
#include
@@ -51,6 +48,32 @@
#define XOTH 00001
#define ALLM 07777 /* all octal mode bits */
+/* Convert OCTAL, which uses one of the traditional octal values, to
+ an internal mode_t value. */
+static mode_t
+octal_to_mode (unsigned int octal)
+{
+ /* Help the compiler optimize the usual case where mode_t uses
+ the traditional octal representation. */
+ return ((S_ISUID == SUID && S_ISGID == SGID && S_ISVTX == SVTX
+ && S_IRUSR == RUSR && S_IWUSR == WUSR && S_IXUSR == XUSR
+ && S_IRGRP == RGRP && S_IWGRP == WGRP && S_IXGRP == XGRP
+ && S_IROTH == ROTH && S_IWOTH == WOTH && S_IXOTH == XOTH)
+ ? octal
+ : (mode_t) ((octal & SUID ? S_ISUID : 0)
+ | (octal & SGID ? S_ISGID : 0)
+ | (octal & SVTX ? S_ISVTX : 0)
+ | (octal & RUSR ? S_IRUSR : 0)
+ | (octal & WUSR ? S_IWUSR : 0)
+ | (octal & XUSR ? S_IXUSR : 0)
+ | (octal & RGRP ? S_IRGRP : 0)
+ | (octal & WGRP ? S_IWGRP : 0)
+ | (octal & XGRP ? S_IXGRP : 0)
+ | (octal & ROTH ? S_IROTH : 0)
+ | (octal & WOTH ? S_IWOTH : 0)
+ | (octal & XOTH ? S_IXOTH : 0)));
+}
+
/* Special operations flags. */
enum
{
@@ -67,30 +90,33 @@ enum
/* Instead of the typical case, copy some existing permissions for
u, g, or o onto the other two. Which of u, g, or o is copied
- is determined by which bits are set in the `value' field. */
+ is determined by which bits are set in the 'value' field. */
MODE_COPY_EXISTING
};
/* Description of a mode change. */
struct mode_change
{
- char op; /* One of "=+-". */
- char flag; /* Special operations flag. */
- mode_t affected; /* Set for u, g, o, or a. */
- mode_t value; /* Bits to add/remove. */
+ char op; /* One of "=+-". */
+ char flag; /* Special operations flag. */
+ mode_t affected; /* Set for u, g, o, or a. */
+ mode_t value; /* Bits to add/remove. */
+ mode_t mentioned; /* Bits explicitly mentioned. */
};
-/* Return a mode_change array with the specified `=ddd'-style
- mode change operation, where NEW_MODE is `ddd'. */
+/* Return a mode_change array with the specified "=ddd"-style
+ mode change operation, where NEW_MODE is "ddd" and MENTIONED
+ contains the bits explicitly mentioned in the mode are MENTIONED. */
static struct mode_change *
-make_node_op_equals (mode_t new_mode)
+make_node_op_equals (mode_t new_mode, mode_t mentioned)
{
struct mode_change *p = xmalloc (2 * sizeof *p);
p->op = '=';
p->flag = MODE_ORDINARY_CHANGE;
p->affected = CHMOD_MODE_BITS;
p->value = new_mode;
+ p->mentioned = mentioned;
p[1].flag = MODE_DONE;
return p;
}
@@ -101,7 +127,7 @@ make_node_op_equals (mode_t new_mode)
the form:
[ugoa...][[+-=][rwxXstugo...]...][,...]
- Return NULL if `mode_string' does not contain a valid
+ Return NULL if 'mode_string' does not contain a valid
representation of file mode change operations. */
struct mode_change *
@@ -110,153 +136,169 @@ mode_compile (char const *mode_string)
/* The array of mode-change directives to be returned. */
struct mode_change *mc;
size_t used = 0;
+ char const *p;
if ('0' <= *mode_string && *mode_string < '8')
{
+ unsigned int octal_mode = 0;
mode_t mode;
- unsigned int octal_value = 0;
+ mode_t mentioned;
+ p = mode_string;
do
- {
- octal_value = 8 * octal_value + *mode_string++ - '0';
- if (ALLM < octal_value)
- return NULL;
- }
- while ('0' <= *mode_string && *mode_string < '8');
-
- /* Help the compiler optimize the usual case where mode_t uses
- the traditional octal representation. */
- mode = ((S_ISUID == SUID && S_ISGID == SGID && S_ISVTX == SVTX
- && S_IRUSR == RUSR && S_IWUSR == WUSR && S_IXUSR == XUSR
- && S_IRGRP == RGRP && S_IWGRP == WGRP && S_IXGRP == XGRP
- && S_IROTH == ROTH && S_IWOTH == WOTH && S_IXOTH == XOTH)
- ? octal_value
- : (mode_t) ((octal_value & SUID ? S_ISUID : 0)
- | (octal_value & SGID ? S_ISGID : 0)
- | (octal_value & SVTX ? S_ISVTX : 0)
- | (octal_value & RUSR ? S_IRUSR : 0)
- | (octal_value & WUSR ? S_IWUSR : 0)
- | (octal_value & XUSR ? S_IXUSR : 0)
- | (octal_value & RGRP ? S_IRGRP : 0)
- | (octal_value & WGRP ? S_IWGRP : 0)
- | (octal_value & XGRP ? S_IXGRP : 0)
- | (octal_value & ROTH ? S_IROTH : 0)
- | (octal_value & WOTH ? S_IWOTH : 0)
- | (octal_value & XOTH ? S_IXOTH : 0)));
-
- return make_node_op_equals (mode);
+ {
+ octal_mode = 8 * octal_mode + *p++ - '0';
+ if (ALLM < octal_mode)
+ return NULL;
+ }
+ while ('0' <= *p && *p < '8');
+
+ if (*p)
+ return NULL;
+
+ mode = octal_to_mode (octal_mode);
+ mentioned = (p - mode_string < 5
+ ? (mode & (S_ISUID | S_ISGID)) | S_ISVTX | S_IRWXUGO
+ : CHMOD_MODE_BITS);
+ return make_node_op_equals (mode, mentioned);
}
/* Allocate enough space to hold the result. */
{
size_t needed = 1;
- char const *p;
for (p = mode_string; *p; p++)
needed += (*p == '=' || *p == '+' || *p == '-');
mc = xnmalloc (needed, sizeof *mc);
}
- /* One loop iteration for each `[ugoa]*([-+=]([rwxXst]*|[ugo]))+'. */
- for (;; mode_string++)
+ /* One loop iteration for each
+ '[ugoa]*([-+=]([rwxXst]*|[ugo]))+|[-+=][0-7]+'. */
+ for (p = mode_string; ; p++)
{
/* Which bits in the mode are operated on. */
mode_t affected = 0;
- /* Turn on all the bits in `affected' for each group given. */
- for (;; mode_string++)
- switch (*mode_string)
- {
- default:
- goto invalid;
- case 'u':
- affected |= S_ISUID | S_IRWXU;
- break;
- case 'g':
- affected |= S_ISGID | S_IRWXG;
- break;
- case 'o':
- affected |= S_ISVTX | S_IRWXO;
- break;
- case 'a':
- affected |= CHMOD_MODE_BITS;
- break;
- case '=': case '+': case '-':
- goto no_more_affected;
- }
+ /* Turn on all the bits in 'affected' for each group given. */
+ for (;; p++)
+ switch (*p)
+ {
+ default:
+ goto invalid;
+ case 'u':
+ affected |= S_ISUID | S_IRWXU;
+ break;
+ case 'g':
+ affected |= S_ISGID | S_IRWXG;
+ break;
+ case 'o':
+ affected |= S_ISVTX | S_IRWXO;
+ break;
+ case 'a':
+ affected |= CHMOD_MODE_BITS;
+ break;
+ case '=': case '+': case '-':
+ goto no_more_affected;
+ }
no_more_affected:;
do
- {
- char op = *mode_string++;
- mode_t value;
- char flag = MODE_COPY_EXISTING;
- struct mode_change *change;
-
- switch (*mode_string++)
- {
- case 'u':
- /* Set the affected bits to the value of the `u' bits
- on the same file. */
- value = S_IRWXU;
- break;
- case 'g':
- /* Set the affected bits to the value of the `g' bits
- on the same file. */
- value = S_IRWXG;
- break;
- case 'o':
- /* Set the affected bits to the value of the `o' bits
- on the same file. */
- value = S_IRWXO;
- break;
-
- default:
- value = 0;
- flag = MODE_ORDINARY_CHANGE;
-
- for (mode_string--;; mode_string++)
- switch (*mode_string)
- {
- case 'r':
- value |= S_IRUSR | S_IRGRP | S_IROTH;
- break;
- case 'w':
- value |= S_IWUSR | S_IWGRP | S_IWOTH;
- break;
- case 'x':
- value |= S_IXUSR | S_IXGRP | S_IXOTH;
- break;
- case 'X':
- flag = MODE_X_IF_ANY_X;
- break;
- case 's':
- /* Set the setuid/gid bits if `u' or `g' is selected. */
- value |= S_ISUID | S_ISGID;
- break;
- case 't':
- /* Set the "save text image" bit if `o' is selected. */
- value |= S_ISVTX;
- break;
- default:
- goto no_more_values;
- }
- no_more_values:;
- }
-
- change = &mc[used++];
- change->op = op;
- change->flag = flag;
- change->affected = affected;
- change->value = value;
- }
- while (*mode_string == '=' || *mode_string == '+'
- || *mode_string == '-');
-
- if (*mode_string != ',')
- break;
+ {
+ char op = *p++;
+ mode_t value;
+ mode_t mentioned = 0;
+ char flag = MODE_COPY_EXISTING;
+ struct mode_change *change;
+
+ switch (*p)
+ {
+ case '0': case '1': case '2': case '3':
+ case '4': case '5': case '6': case '7':
+ {
+ unsigned int octal_mode = 0;
+
+ do
+ {
+ octal_mode = 8 * octal_mode + *p++ - '0';
+ if (ALLM < octal_mode)
+ return NULL;
+ }
+ while ('0' <= *p && *p < '8');
+
+ if (affected || (*p && *p != ','))
+ return NULL;
+ affected = mentioned = CHMOD_MODE_BITS;
+ value = octal_to_mode (octal_mode);
+ flag = MODE_ORDINARY_CHANGE;
+ break;
+ }
+
+ case 'u':
+ /* Set the affected bits to the value of the "u" bits
+ on the same file. */
+ value = S_IRWXU;
+ p++;
+ break;
+ case 'g':
+ /* Set the affected bits to the value of the "g" bits
+ on the same file. */
+ value = S_IRWXG;
+ p++;
+ break;
+ case 'o':
+ /* Set the affected bits to the value of the "o" bits
+ on the same file. */
+ value = S_IRWXO;
+ p++;
+ break;
+
+ default:
+ value = 0;
+ flag = MODE_ORDINARY_CHANGE;
+
+ for (;; p++)
+ switch (*p)
+ {
+ case 'r':
+ value |= S_IRUSR | S_IRGRP | S_IROTH;
+ break;
+ case 'w':
+ value |= S_IWUSR | S_IWGRP | S_IWOTH;
+ break;
+ case 'x':
+ value |= S_IXUSR | S_IXGRP | S_IXOTH;
+ break;
+ case 'X':
+ flag = MODE_X_IF_ANY_X;
+ break;
+ case 's':
+ /* Set the setuid/gid bits if 'u' or 'g' is selected. */
+ value |= S_ISUID | S_ISGID;
+ break;
+ case 't':
+ /* Set the "save text image" bit if 'o' is selected. */
+ value |= S_ISVTX;
+ break;
+ default:
+ goto no_more_values;
+ }
+ no_more_values:;
+ }
+
+ change = &mc[used++];
+ change->op = op;
+ change->flag = flag;
+ change->affected = affected;
+ change->value = value;
+ change->mentioned =
+ (mentioned ? mentioned : affected ? affected & value : value);
+ }
+ while (*p == '=' || *p == '+' || *p == '-');
+
+ if (*p != ',')
+ break;
}
- if (*mode_string == 0)
+ if (*p == 0)
{
mc[used].flag = MODE_DONE;
return mc;
@@ -277,74 +319,96 @@ mode_create_from_ref (const char *ref_file)
if (stat (ref_file, &ref_stats) != 0)
return NULL;
- return make_node_op_equals (ref_stats.st_mode);
+ return make_node_op_equals (ref_stats.st_mode, CHMOD_MODE_BITS);
}
-/* Return file mode OLDMODE, adjusted as indicated by the list of change
- operations CHANGES, which are interpreted assuming the umask is
- UMASK_VALUE. If OLDMODE is a directory, the type `X'
- change affects it even if no execute bits were set in OLDMODE.
- The returned value has the S_IFMT bits cleared. */
+/* Return the file mode bits of OLDMODE (which is the mode of a
+ directory if DIR), assuming the umask is UMASK_VALUE, adjusted as
+ indicated by the list of change operations CHANGES. If DIR, the
+ type 'X' change affects the returned value even if no execute bits
+ were set in OLDMODE, and set user and group ID bits are preserved
+ unless CHANGES mentioned them. If PMODE_BITS is not null, store into
+ *PMODE_BITS a mask denoting file mode bits that are affected by
+ CHANGES.
+
+ The returned value and *PMODE_BITS contain only file mode bits.
+ For example, they have the S_IFMT bits cleared on a standard
+ Unix-like host. */
mode_t
-mode_adjust (mode_t oldmode, struct mode_change const *changes,
- mode_t umask_value)
+mode_adjust (mode_t oldmode, bool dir, mode_t umask_value,
+ struct mode_change const *changes, mode_t *pmode_bits)
{
/* The adjusted mode. */
mode_t newmode = oldmode & CHMOD_MODE_BITS;
+ /* File mode bits that CHANGES cares about. */
+ mode_t mode_bits = 0;
+
for (; changes->flag != MODE_DONE; changes++)
{
mode_t affected = changes->affected;
+ mode_t omit_change =
+ (dir ? S_ISUID | S_ISGID : 0) & ~ changes->mentioned;
mode_t value = changes->value;
switch (changes->flag)
- {
- case MODE_ORDINARY_CHANGE:
- break;
-
- case MODE_COPY_EXISTING:
- /* Isolate in `value' the bits in `newmode' to copy. */
- value &= newmode;
-
- /* Copy the isolated bits to the other two parts. */
- value |= ((value & (S_IRUSR | S_IRGRP | S_IROTH)
- ? S_IRUSR | S_IRGRP | S_IROTH : 0)
- | (value & (S_IWUSR | S_IWGRP | S_IWOTH)
- ? S_IWUSR | S_IWGRP | S_IWOTH : 0)
- | (value & (S_IXUSR | S_IXGRP | S_IXOTH)
- ? S_IXUSR | S_IXGRP | S_IXOTH : 0));
- break;
-
- case MODE_X_IF_ANY_X:
- /* Affect the execute bits if execute bits are already set
- or if the file is a directory. */
- if ((newmode & (S_IXUSR | S_IXGRP | S_IXOTH)) || S_ISDIR (oldmode))
- value |= S_IXUSR | S_IXGRP | S_IXOTH;
- break;
- }
+ {
+ case MODE_ORDINARY_CHANGE:
+ break;
+
+ case MODE_COPY_EXISTING:
+ /* Isolate in 'value' the bits in 'newmode' to copy. */
+ value &= newmode;
+
+ /* Copy the isolated bits to the other two parts. */
+ value |= ((value & (S_IRUSR | S_IRGRP | S_IROTH)
+ ? S_IRUSR | S_IRGRP | S_IROTH : 0)
+ | (value & (S_IWUSR | S_IWGRP | S_IWOTH)
+ ? S_IWUSR | S_IWGRP | S_IWOTH : 0)
+ | (value & (S_IXUSR | S_IXGRP | S_IXOTH)
+ ? S_IXUSR | S_IXGRP | S_IXOTH : 0));
+ break;
+
+ case MODE_X_IF_ANY_X:
+ /* Affect the execute bits if execute bits are already set
+ or if the file is a directory. */
+ if ((newmode & (S_IXUSR | S_IXGRP | S_IXOTH)) | dir)
+ value |= S_IXUSR | S_IXGRP | S_IXOTH;
+ break;
+ }
/* If WHO was specified, limit the change to the affected bits.
- Otherwise, apply the umask. */
- value &= (affected ? affected : ~umask_value);
+ Otherwise, apply the umask. Either way, omit changes as
+ requested. */
+ value &= (affected ? affected : ~umask_value) & ~ omit_change;
switch (changes->op)
- {
- case '=':
- /* If WHO was specified, preserve the previous values of
- bits that are not affected by this change operation.
- Otherwise, clear all the bits. */
- newmode = (affected ? newmode & ~affected : 0);
- /* Fall through. */
- case '+':
- newmode |= value;
- break;
-
- case '-':
- newmode &= ~value;
- break;
- }
+ {
+ case '=':
+ /* If WHO was specified, preserve the previous values of
+ bits that are not affected by this change operation.
+ Otherwise, clear all the bits. */
+ {
+ mode_t preserved = (affected ? ~affected : 0) | omit_change;
+ mode_bits |= CHMOD_MODE_BITS & ~preserved;
+ newmode = (newmode & preserved) | value;
+ break;
+ }
+
+ case '+':
+ mode_bits |= value;
+ newmode |= value;
+ break;
+
+ case '-':
+ mode_bits |= value;
+ newmode &= ~value;
+ break;
+ }
}
+ if (pmode_bits)
+ *pmode_bits = mode_bits;
return newmode;
}