+
+/* Number of user commands executed during this session. */
+
+static int command_count = 0;
+
+/* Add the user command COMMAND to the input history list. */
+
+void
+gdb_add_history (const char *command)
+{
+ command_count++;
+
+ if (history_remove_duplicates != 0)
+ {
+ int lookbehind;
+ int lookbehind_threshold;
+
+ /* The lookbehind threshold for finding a duplicate history entry is
+ bounded by command_count because we can't meaningfully delete
+ history entries that are already stored in the history file since
+ the history file is appended to. */
+ if (history_remove_duplicates == -1
+ || history_remove_duplicates > command_count)
+ lookbehind_threshold = command_count;
+ else
+ lookbehind_threshold = history_remove_duplicates;
+
+ using_history ();
+ for (lookbehind = 0; lookbehind < lookbehind_threshold; lookbehind++)
+ {
+ HIST_ENTRY *temp = previous_history ();
+
+ if (temp == NULL)
+ break;
+
+ if (strcmp (temp->line, command) == 0)
+ {
+ HIST_ENTRY *prev = remove_history (where_history ());
+ command_count--;
+ free_history_entry (prev);
+ break;
+ }
+ }
+ using_history ();
+ }
+
+ add_history (command);
+}
+
+/* Safely append new history entries to the history file in a corruption-free
+ way using an intermediate local history file. */
+
+static void
+gdb_safe_append_history (void)
+{
+ int ret, saved_errno;
+ char *local_history_filename;
+ struct cleanup *old_chain;
+
+ local_history_filename
+ = xstrprintf ("%s-gdb%d~", history_filename, getpid ());
+ old_chain = make_cleanup (xfree, local_history_filename);
+
+ ret = rename (history_filename, local_history_filename);
+ saved_errno = errno;
+ if (ret < 0 && saved_errno != ENOENT)
+ {
+ warning (_("Could not rename %s to %s: %s"),
+ history_filename, local_history_filename,
+ safe_strerror (saved_errno));
+ }
+ else
+ {
+ if (ret < 0)
+ {
+ /* If the rename failed with ENOENT then either the global history
+ file never existed in the first place or another GDB process is
+ currently appending to it (and has thus temporarily renamed it).
+ Since we can't distinguish between these two cases, we have to
+ conservatively assume the first case and therefore must write out
+ (not append) our known history to our local history file and try
+ to move it back anyway. Otherwise a global history file would
+ never get created! */
+ gdb_assert (saved_errno == ENOENT);
+ write_history (local_history_filename);
+ }
+ else
+ {
+ append_history (command_count, local_history_filename);
+ if (history_is_stifled ())
+ history_truncate_file (local_history_filename, history_max_entries);
+ }
+
+ ret = rename (local_history_filename, history_filename);
+ saved_errno = errno;
+ if (ret < 0 && saved_errno != EEXIST)
+ warning (_("Could not rename %s to %s: %s"),
+ local_history_filename, history_filename,
+ safe_strerror (saved_errno));
+ }
+
+ do_cleanups (old_chain);
+}
+
+/* Read one line from the command input stream `instream' into a local
+ static buffer. The buffer is made bigger as necessary. Returns
+ the address of the start of the line.
projects / deliverable / binutils-gdb.git / blobdiff