Mercurial > hg > octave-nkf > gnulib-hg
changeset 1769:bc0ac225f0a8
(make_node_op_equals): New function.
(mode_append_entry): Likewise.
(mode_compile): When none of [ugoa] is specified in an `=OP' change
mode request, insert a `=0' entry into the linked list so that all
bits are cleared first. Use the new functions.
author | Jim Meyering <jim@meyering.net> |
---|---|
date | Tue, 30 Mar 1999 04:51:08 +0000 |
parents | d12253dc9dbb |
children | a31477086c7f |
files | lib/modechange.c |
diffstat | 1 files changed, 79 insertions(+), 34 deletions(-) [+] |
line wrap: on
line diff
--- a/lib/modechange.c +++ b/lib/modechange.c @@ -72,6 +72,42 @@ return i; } +/* 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 (int 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 = 07777; /* 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 @@ -89,41 +125,44 @@ mode_compile (const char *mode_string, unsigned int masked_ops) { struct mode_change *head; /* First element of the linked list. */ - struct mode_change *change; /* An element of the linked list. */ + struct mode_change *tail; /* An element of the linked list. */ int i; /* General purpose temporary. */ int umask_value; /* The umask value (surprise). */ - unsigned short affected_bits; /* Which bits in the mode are operated on. */ - unsigned short affected_masked; /* `affected_bits' modified by umask. */ - unsigned ops_to_mask; /* Operators to actually use umask on. */ + + head = NULL; +#ifdef lint + tail = NULL; +#endif i = oatoi (mode_string); if (i >= 0) { + struct mode_change *p; if (i > 07777) return MODE_INVALID; - head = talloc (struct mode_change); - if (head == NULL) + p = make_node_op_equals (i); + if (p == NULL) return MODE_MEMORY_EXHAUSTED; - head->next = NULL; - head->op = '='; - head->flags = 0; - head->value = i; - head->affected = 07777; /* Affect all permissions. */ + mode_append_entry (&head, &tail, p); return head; } umask_value = umask (0); umask (umask_value); /* Restore the old value. */ - - head = NULL; -#ifdef lint - change = NULL; -#endif --mode_string; /* One loop iteration for each "ugoa...=+-rwxXstugo...[=+-rwxXstugo...]". */ do { + /* Which bits in the mode are operated on. */ + unsigned short affected_bits = 0; + /* `affected_bits' modified by umask. */ + unsigned short 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. */ @@ -149,37 +188,39 @@ no_more_affected: /* If none specified, affect all bits, except perhaps those set in the umask. */ - if (affected_bits == 0) + if (affected_bits) + who_specified_p = 1; + else { + who_specified_p = 0; affected_bits = 07777; ops_to_mask = masked_ops; } while (*mode_string == '=' || *mode_string == '+' || *mode_string == '-') { - /* Add the element to the tail of the list, so the operations - are performed in the correct order. */ - if (head == NULL) + struct mode_change *change = talloc (struct mode_change); + if (change == NULL) { - head = talloc (struct mode_change); - if (head == NULL) - return MODE_MEMORY_EXHAUSTED; - change = head; - } - else - { - change->next = talloc (struct mode_change); - if (change->next == NULL) - { - mode_free (head); - return MODE_MEMORY_EXHAUSTED; - } - change = change->next; + 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)) @@ -188,6 +229,10 @@ 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)