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#include "rsync.h"
extern int orig_umask;
#define FLAG_X_KEEP (1<<0)
#define FLAG_DIRS_ONLY (1<<1)
#define FLAG_FILES_ONLY (1<<2)
struct chmod_mode_struct {
struct chmod_mode_struct *next;
int ModeAND, ModeOR;
char flags;
};
#define CHMOD_ADD 1
#define CHMOD_SUB 2
#define CHMOD_EQ 3
#define STATE_ERROR 0
#define STATE_1ST_HALF 1
#define STATE_2ND_HALF 2
/* Parse a chmod-style argument, and break it down into one or more AND/OR
* pairs in a linked list. We use a state machine to walk through the
* options. */
struct chmod_mode_struct *parse_chmod(char *modestr)
{
int state = STATE_1ST_HALF;
int where = 0, what = 0, op = 0, topbits = 0, topoct = 0, flags = 0;
struct chmod_mode_struct *first_mode = NULL, *curr_mode = NULL,
*prev_mode = NULL;
while (state != STATE_ERROR) {
if (!*modestr || *modestr == ',') {
int bits;
if (!op) {
state = STATE_ERROR;
break;
}
prev_mode = curr_mode;
curr_mode = new_array(struct chmod_mode_struct, 1);
if (prev_mode)
prev_mode->next = curr_mode;
else
first_mode = curr_mode;
curr_mode->next = NULL;
if (where)
bits = where * what;
else {
where = 0111;
bits = (where * what) & ~orig_umask;
}
switch (op) {
case CHMOD_ADD:
curr_mode->ModeAND = 07777;
curr_mode->ModeOR = bits + topoct;
break;
case CHMOD_SUB:
curr_mode->ModeAND = 07777 - bits - topoct;
curr_mode->ModeOR = 0;
break;
case CHMOD_EQ:
curr_mode->ModeAND = 07777 - (where * 7) - (topoct ? topbits : 0);
curr_mode->ModeOR = bits + topoct;
break;
}
curr_mode->flags = flags;
if (!*modestr)
break;
modestr++;
state = STATE_1ST_HALF;
where = what = op = topoct = topbits = flags = 0;
}
if (state != STATE_2ND_HALF) {
switch (*modestr) {
case 'D':
if (flags & FLAG_FILES_ONLY)
state = STATE_ERROR;
flags |= FLAG_DIRS_ONLY;
break;
case 'F':
if (flags & FLAG_DIRS_ONLY)
state = STATE_ERROR;
flags |= FLAG_FILES_ONLY;
break;
case 'u':
where |= 0100;
topbits |= 04000;
break;
case 'g':
where |= 0010;
topbits |= 02000;
break;
case 'o':
where |= 0001;
break;
case 'a':
where |= 0111;
break;
case '+':
op = CHMOD_ADD;
state = STATE_2ND_HALF;
break;
case '-':
op = CHMOD_SUB;
state = STATE_2ND_HALF;
break;
case '=':
op = CHMOD_EQ;
state = STATE_2ND_HALF;
break;
default:
state = STATE_ERROR;
break;
}
} else {
switch (*modestr) {
case 'r':
what |= 4;
break;
case 'w':
what |= 2;
break;
case 'X':
flags |= FLAG_X_KEEP;
/* FALL THROUGH */
case 'x':
what |= 1;
break;
case 's':
if (topbits)
topoct |= topbits;
else
topoct = 04000;
break;
case 't':
topoct |= 01000;
break;
default:
state = STATE_ERROR;
break;
}
}
modestr++;
}
if (state == STATE_ERROR) {
free_chmod_mode(first_mode);
first_mode = NULL;
}
return first_mode;
}
/* Takes an existing file permission and a list of AND/OR changes, and
* create a new permissions. */
int tweak_mode(int mode, struct chmod_mode_struct *chmod_modes)
{
int IsX = mode & 0111;
int NonPerm = mode & ~07777;
for ( ; chmod_modes; chmod_modes = chmod_modes->next) {
if ((chmod_modes->flags & FLAG_DIRS_ONLY) && !S_ISDIR(NonPerm))
continue;
if ((chmod_modes->flags & FLAG_FILES_ONLY) && S_ISDIR(NonPerm))
continue;
mode &= chmod_modes->ModeAND;
if ((chmod_modes->flags & FLAG_X_KEEP) && !IsX && !S_ISDIR(NonPerm))
mode |= chmod_modes->ModeOR & ~0111;
else
mode |= chmod_modes->ModeOR;
}
return mode | NonPerm;
}
/* Free the linked list created by parse_chmod. */
int free_chmod_mode(struct chmod_mode_struct *chmod_modes)
{
struct chmod_mode_struct *next;
while (chmod_modes) {
next = chmod_modes->next;
free(chmod_modes);
chmod_modes = next;
}
return 0;
}
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