X-Git-Url: https://git.dogcows.com/gitweb?a=blobdiff_plain;f=lib%2Fmodechange.c;fp=lib%2Fmodechange.c;h=0000000000000000000000000000000000000000;hb=c30c4ffb9fc874aafea6f6c91f3fc78595db4154;hp=ef484c0fbc113638488b8f6c290c41e42353ad9c;hpb=b216fed6340d073d33351145be033ecc5b903c7a;p=chaz%2Ftar diff --git a/lib/modechange.c b/lib/modechange.c deleted file mode 100644 index ef484c0..0000000 --- a/lib/modechange.c +++ /dev/null @@ -1,445 +0,0 @@ -/* modechange.c -- file mode manipulation - Copyright (C) 1989, 1990, 1997, 1998, 1999 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 2, 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, write to the Free Software Foundation, - Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ - -/* Written by David MacKenzie */ - -/* The ASCII mode string is compiled into a linked list 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 "modechange.h" -#include -#include "xstrtol.h" - -#if STDC_HEADERS -# include -#else -char *malloc (); -#endif - -#ifndef NULL -# define NULL 0 -#endif - -#if STAT_MACROS_BROKEN -# undef S_ISDIR -#endif - -#if !defined(S_ISDIR) && defined(S_IFDIR) -# define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR) -#endif - -#ifndef S_ISUID -# define S_ISUID 04000 -#endif -#ifndef S_ISGID -# define S_ISGID 04000 -#endif -#ifndef S_ISVTX -# define S_ISVTX 01000 -#endif -#ifndef S_IRUSR -# define S_IRUSR 0400 -#endif -#ifndef S_IWUSR -# define S_IWUSR 0200 -#endif -#ifndef S_IXUSR -# define S_IXUSR 0100 -#endif -#ifndef S_IRGRP -# define S_IRGRP 0040 -#endif -#ifndef S_IWGRP -# define S_IWGRP 0020 -#endif -#ifndef S_IXGRP -# define S_IXGRP 0010 -#endif -#ifndef S_IROTH -# define S_IROTH 0004 -#endif -#ifndef S_IWOTH -# define S_IWOTH 0002 -#endif -#ifndef S_IXOTH -# define S_IXOTH 0001 -#endif -#ifndef S_IRWXU -# define S_IRWXU 0700 -#endif -#ifndef S_IRWXG -# define S_IRWXG 0070 -#endif -#ifndef S_IRWXO -# define S_IRWXO 0007 -#endif - -/* All the mode bits that can be affected by chmod. */ -#define CHMOD_MODE_BITS \ - (S_ISUID | S_ISGID | S_ISVTX | S_IRWXU | S_IRWXG | S_IRWXO) - -/* Return newly allocated memory to hold one element of type TYPE. */ -#define talloc(type) ((type *) malloc (sizeof (type))) - -/* Create a mode_change entry with the specified `=ddd'-style - mode change operation, where NEW_MODE is `ddd'. Return the - new entry, or NULL upon failure. */ - -static struct mode_change * -make_node_op_equals (mode_t new_mode) -{ - struct mode_change *p; - p = talloc (struct mode_change); - if (p == NULL) - return p; - p->next = NULL; - p->op = '='; - p->flags = 0; - p->value = new_mode; - p->affected = CHMOD_MODE_BITS; /* Affect all permissions. */ - return p; -} - -/* Append entry E to the end of the link list with the specified - HEAD and TAIL. */ - -static void -mode_append_entry (struct mode_change **head, - struct mode_change **tail, - struct mode_change *e) -{ - if (*head == NULL) - *head = *tail = e; - else - { - (*tail)->next = e; - *tail = e; - } -} - -/* Return a linked list of file mode change operations created from - MODE_STRING, an ASCII string that contains either an octal number - specifying an absolute mode, or symbolic mode change operations with - the form: - [ugoa...][[+-=][rwxXstugo...]...][,...] - MASKED_OPS is a bitmask indicating which symbolic mode operators (=+-) - should not affect bits set in the umask when no users are given. - Operators not selected in MASKED_OPS ignore the umask. - - Return MODE_INVALID if `mode_string' does not contain a valid - representation of file mode change operations; - return MODE_MEMORY_EXHAUSTED if there is insufficient memory. */ - -struct mode_change * -mode_compile (const char *mode_string, unsigned int masked_ops) -{ - struct mode_change *head; /* First element of the linked list. */ - struct mode_change *tail; /* An element of the linked list. */ - uintmax_t mode_value; /* The mode value, if octal. */ - char *string_end; /* Pointer to end of parsed value. */ - mode_t umask_value; /* The umask value (surprise). */ - - head = NULL; -#ifdef lint - tail = NULL; -#endif - - if (xstrtoumax (mode_string, &string_end, 8, &mode_value, "") == LONGINT_OK) - { - struct mode_change *p; - if (mode_value != (mode_value & CHMOD_MODE_BITS)) - return MODE_INVALID; - p = make_node_op_equals ((mode_t) mode_value); - if (p == NULL) - return MODE_MEMORY_EXHAUSTED; - mode_append_entry (&head, &tail, p); - return head; - } - - umask_value = umask (0); - umask (umask_value); /* Restore the old value. */ - --mode_string; - - /* One loop iteration for each "ugoa...=+-rwxXstugo...[=+-rwxXstugo...]". */ - do - { - /* Which bits in the mode are operated on. */ - mode_t affected_bits = 0; - /* `affected_bits' modified by umask. */ - mode_t affected_masked; - /* Operators to actually use umask on. */ - unsigned ops_to_mask = 0; - - int who_specified_p; - - affected_bits = 0; - ops_to_mask = 0; - /* Turn on all the bits in `affected_bits' for each group given. */ - for (++mode_string;; ++mode_string) - switch (*mode_string) - { - case 'u': - affected_bits |= S_ISUID | S_IRWXU; - break; - case 'g': - affected_bits |= S_ISGID | S_IRWXG; - break; - case 'o': - affected_bits |= S_ISVTX | S_IRWXO; - break; - case 'a': - affected_bits |= CHMOD_MODE_BITS; - break; - default: - goto no_more_affected; - } - - no_more_affected: - /* If none specified, affect all bits, except perhaps those - set in the umask. */ - if (affected_bits) - who_specified_p = 1; - else - { - who_specified_p = 0; - affected_bits = CHMOD_MODE_BITS; - ops_to_mask = masked_ops; - } - - while (*mode_string == '=' || *mode_string == '+' || *mode_string == '-') - { - struct mode_change *change = talloc (struct mode_change); - if (change == NULL) - { - mode_free (head); - return MODE_MEMORY_EXHAUSTED; - } - - change->next = NULL; - change->op = *mode_string; /* One of "=+-". */ - affected_masked = affected_bits; - - /* Per the Single Unix Spec, if `who' is not specified and the - `=' operator is used, then clear all the bits first. */ - if (!who_specified_p && - ops_to_mask & (*mode_string == '=' ? MODE_MASK_EQUALS : 0)) - { - struct mode_change *p = make_node_op_equals (0); - if (p == NULL) - return MODE_MEMORY_EXHAUSTED; - mode_append_entry (&head, &tail, p); - } - - if (ops_to_mask & (*mode_string == '=' ? MODE_MASK_EQUALS - : *mode_string == '+' ? MODE_MASK_PLUS - : MODE_MASK_MINUS)) - affected_masked &= ~umask_value; - change->affected = affected_masked; - change->value = 0; - change->flags = 0; - - /* Add the element to the tail of the list, so the operations - are performed in the correct order. */ - mode_append_entry (&head, &tail, change); - - /* Set `value' according to the bits set in `affected_masked'. */ - for (++mode_string;; ++mode_string) - switch (*mode_string) - { - case 'r': - change->value |= ((S_IRUSR | S_IRGRP | S_IROTH) - & affected_masked); - break; - case 'w': - change->value |= ((S_IWUSR | S_IWGRP | S_IWOTH) - & affected_masked); - break; - case 'X': - change->flags |= MODE_X_IF_ANY_X; - /* Fall through. */ - case 'x': - change->value |= ((S_IXUSR | S_IXGRP | S_IXOTH) - & affected_masked); - break; - case 's': - /* Set the setuid/gid bits if `u' or `g' is selected. */ - change->value |= (S_ISUID | S_ISGID) & affected_masked; - break; - case 't': - /* Set the "save text image" bit if `o' is selected. */ - change->value |= S_ISVTX & affected_masked; - break; - case 'u': - /* Set the affected bits to the value of the `u' bits - on the same file. */ - if (change->value) - goto invalid; - change->value = S_IRWXU; - change->flags |= MODE_COPY_EXISTING; - break; - case 'g': - /* Set the affected bits to the value of the `g' bits - on the same file. */ - if (change->value) - goto invalid; - change->value = S_IRWXG; - change->flags |= MODE_COPY_EXISTING; - break; - case 'o': - /* Set the affected bits to the value of the `o' bits - on the same file. */ - if (change->value) - goto invalid; - change->value = S_IRWXO; - change->flags |= MODE_COPY_EXISTING; - break; - default: - goto no_more_values; - } - no_more_values:; - } - } while (*mode_string == ','); - if (*mode_string == 0) - return head; -invalid: - mode_free (head); - return MODE_INVALID; -} - -/* Return a file mode change operation that sets permissions to match those - of REF_FILE. Return MODE_BAD_REFERENCE if REF_FILE can't be accessed. */ - -struct mode_change * -mode_create_from_ref (const char *ref_file) -{ - struct mode_change *change; /* the only change element */ - struct stat ref_stats; - - if (stat (ref_file, &ref_stats)) - return MODE_BAD_REFERENCE; - - change = talloc (struct mode_change); - - if (change == NULL) - return MODE_MEMORY_EXHAUSTED; - - change->op = '='; - change->flags = 0; - change->affected = CHMOD_MODE_BITS; - change->value = ref_stats.st_mode; - change->next = NULL; - - return change; -} - -/* Return file mode OLDMODE, adjusted as indicated by the list of change - operations CHANGES. 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. */ - -mode_t -mode_adjust (mode_t oldmode, const struct mode_change *changes) -{ - mode_t newmode; /* The adjusted mode and one operand. */ - mode_t value; /* The other operand. */ - - newmode = oldmode & CHMOD_MODE_BITS; - - for (; changes; changes = changes->next) - { - if (changes->flags & MODE_COPY_EXISTING) - { - /* Isolate in `value' the bits in `newmode' to copy, given in - the mask `changes->value'. */ - value = newmode & changes->value; - - if (changes->value & S_IRWXU) - /* Copy `u' permissions onto `g' and `o'. */ - value |= ((value & S_IRUSR ? S_IRGRP | S_IROTH : 0) - | (value & S_IWUSR ? S_IWGRP | S_IROTH : 0) - | (value & S_IXUSR ? S_IXGRP | S_IXOTH : 0)); - else if (changes->value & S_IRWXG) - /* Copy `g' permissions onto `u' and `o'. */ - value |= ((value & S_IRGRP ? S_IRUSR | S_IROTH : 0) - | (value & S_IWGRP ? S_IWUSR | S_IROTH : 0) - | (value & S_IXGRP ? S_IXUSR | S_IXOTH : 0)); - else - /* Copy `o' permissions onto `u' and `g'. */ - value |= ((value & S_IROTH ? S_IRUSR | S_IRGRP : 0) - | (value & S_IWOTH ? S_IWUSR | S_IRGRP : 0) - | (value & S_IXOTH ? S_IXUSR | S_IXGRP : 0)); - - /* In order to change only `u', `g', or `o' permissions, - or some combination thereof, clear unselected bits. - This can not be done in mode_compile because the value - to which the `changes->affected' mask is applied depends - on the old mode of each file. */ - value &= changes->affected; - } - else - { - value = changes->value; - /* If `X', do not affect the execute bits if the file is not a - directory and no execute bits are already set. */ - if ((changes->flags & MODE_X_IF_ANY_X) - && !S_ISDIR (oldmode) - && (newmode & (S_IXUSR | S_IXGRP | S_IXOTH)) == 0) - /* Clear the execute bits. */ - value &= ~ (S_IXUSR | S_IXGRP | S_IXOTH); - } - - switch (changes->op) - { - case '=': - /* Preserve the previous values in `newmode' of bits that are - not affected by this change operation. */ - newmode = (newmode & ~changes->affected) | value; - break; - case '+': - newmode |= value; - break; - case '-': - newmode &= ~value; - break; - } - } - return newmode; -} - -/* Free the memory used by the list of file mode change operations - CHANGES. */ - -void -mode_free (register struct mode_change *changes) -{ - register struct mode_change *next; - - while (changes) - { - next = changes->next; - free (changes); - changes = next; - } -}