[git commit] vi: clear undo buffer when we change to another file
Denys Vlasenko
vda.linux at googlemail.com
Thu Apr 3 10:47:48 UTC 2014
commit: http://git.busybox.net/busybox/commit/?id=e7430867a8ad61bbea20d05fc2f9fc5094e211dc
branch: http://git.busybox.net/busybox/commit/?id=refs/heads/master
function old new delta
init_text_buffer 156 190 +34
undo_push 360 382 +22
count_lines 74 72 -2
undo_pop 246 222 -24
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/2 up/down: 56/-26) Total: 30 bytes
Signed-off-by: Denys Vlasenko <vda.linux at googlemail.com>
---
editors/vi.c | 156 ++++++++++++++++++++++++++++++++--------------------------
1 files changed, 87 insertions(+), 69 deletions(-)
diff --git a/editors/vi.c b/editors/vi.c
index 71086c9..a978e0f 100644
--- a/editors/vi.c
+++ b/editors/vi.c
@@ -306,8 +306,8 @@ struct globals {
smallint editing; // >0 while we are editing a file
// [code audit says "can be 0, 1 or 2 only"]
smallint cmd_mode; // 0=command 1=insert 2=replace
- int file_modified; // buffer contents changed (counter, not flag!)
- int last_file_modified; // = -1;
+ int modified_count; // buffer contents changed if !0
+ int last_modified_count; // = -1;
int save_argc; // how many file names on cmd line
int cmdcnt; // repetition count
unsigned rows, columns; // the terminal screen is this size
@@ -378,37 +378,37 @@ struct globals {
char scr_out_buf[MAX_SCR_COLS + MAX_TABSTOP * 2];
#if ENABLE_FEATURE_VI_UNDO
// undo_push() operations
-#define UNDO_INS 0
-#define UNDO_DEL 1
-#define UNDO_INS_CHAIN 2
-#define UNDO_DEL_CHAIN 3
+#define UNDO_INS 0
+#define UNDO_DEL 1
+#define UNDO_INS_CHAIN 2
+#define UNDO_DEL_CHAIN 3
// UNDO_*_QUEUED must be equal to UNDO_xxx ORed with UNDO_QUEUED_FLAG
#define UNDO_QUEUED_FLAG 4
-#define UNDO_INS_QUEUED 4
-#define UNDO_DEL_QUEUED 5
-#define UNDO_USE_SPOS 32
-#define UNDO_EMPTY 64
+#define UNDO_INS_QUEUED 4
+#define UNDO_DEL_QUEUED 5
+#define UNDO_USE_SPOS 32
+#define UNDO_EMPTY 64
// Pass-through flags for functions that can be undone
-#define NO_UNDO 0
-#define ALLOW_UNDO 1
+#define NO_UNDO 0
+#define ALLOW_UNDO 1
#define ALLOW_UNDO_CHAIN 2
-#if ENABLE_FEATURE_VI_UNDO_QUEUE
+# if ENABLE_FEATURE_VI_UNDO_QUEUE
#define ALLOW_UNDO_QUEUED 3
char undo_queue_state;
int undo_q;
char *undo_queue_spos; // Start position of queued operation
char undo_queue[CONFIG_FEATURE_VI_UNDO_QUEUE_MAX];
-#else
+# else
// If undo queuing disabled, don't invoke the missing queue logic
#define ALLOW_UNDO_QUEUED 1
-#endif /* ENABLE_FEATURE_VI_UNDO_QUEUE */
+# endif
struct undo_object {
struct undo_object *prev; // Linking back avoids list traversal (LIFO)
- int u_type; // 0=deleted, 1=inserted, 2=swapped
int start; // Offset where the data should be restored/deleted
int length; // total data size
- char *undo_text; // ptr to text that will be inserted
+ uint8_t u_type; // 0=deleted, 1=inserted, 2=swapped
+ char undo_text[1]; // text that was deleted (if deletion)
} *undo_stack_tail;
#endif /* ENABLE_FEATURE_VI_UNDO */
@@ -423,8 +423,8 @@ struct globals {
#define vi_setops (G.vi_setops )
#define editing (G.editing )
#define cmd_mode (G.cmd_mode )
-#define file_modified (G.file_modified )
-#define last_file_modified (G.last_file_modified )
+#define modified_count (G.modified_count )
+#define last_modified_count (G.last_modified_count)
#define save_argc (G.save_argc )
#define cmdcnt (G.cmdcnt )
#define rows (G.rows )
@@ -485,7 +485,7 @@ struct globals {
#define INIT_G() do { \
SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
- last_file_modified = -1; \
+ last_modified_count = -1; \
/* "" but has space for 2 chars: */ \
IF_FEATURE_VI_SEARCH(last_search_pattern = xzalloc(2);) \
} while (0)
@@ -608,6 +608,7 @@ static char what_reg(void); // what is letter of current YDreg
static void check_context(char); // remember context for '' command
#endif
#if ENABLE_FEATURE_VI_UNDO
+static void flush_undo_data(void);
static void undo_push(char *, unsigned int, unsigned char); // Push an operation on the undo stack
static void undo_pop(void); // Undo the last operation
# if ENABLE_FEATURE_VI_UNDO_QUEUE
@@ -616,6 +617,7 @@ static void undo_queue_commit(void); // Flush any queued objects to the undo sta
# define undo_queue_commit() ((void)0)
# endif
#else
+#define flush_undo_data() ((void)0)
#define undo_queue_commit() ((void)0)
#endif
@@ -725,6 +727,8 @@ static int init_text_buffer(char *fn)
int rc;
int size = file_size(fn); // file size. -1 means does not exist.
+ flush_undo_data();
+
/* allocate/reallocate text buffer */
free(text);
text_size = size + 10240;
@@ -735,14 +739,14 @@ static int init_text_buffer(char *fn)
current_filename = xstrdup(fn);
}
if (size < 0) {
- // file dont exist. Start empty buf with dummy line
+ // file doesnt exist. Start empty buf with dummy line
char_insert(text, '\n', NO_UNDO);
rc = 0;
} else {
rc = file_insert(fn, text, 1);
}
- file_modified = 0;
- last_file_modified = -1;
+ modified_count = 0;
+ last_modified_count = -1;
#if ENABLE_FEATURE_VI_YANKMARK
/* init the marks. */
memset(mark, 0, sizeof(mark));
@@ -1124,7 +1128,7 @@ static void colon(char *buf)
dot_skip_over_ws();
} else if (strncmp(cmd, "edit", i) == 0) { // Edit a file
// don't edit, if the current file has been modified
- if (file_modified && !useforce) {
+ if (modified_count && !useforce) {
status_line_bold("No write since last change (:%s! overrides)", cmd);
goto ret;
}
@@ -1227,7 +1231,7 @@ static void colon(char *buf)
goto ret;
}
// don't exit if the file been modified
- if (file_modified) {
+ if (modified_count) {
status_line_bold("No write since last change (:%s! overrides)", cmd);
goto ret;
}
@@ -1280,10 +1284,10 @@ static void colon(char *buf)
// if the insert is before "dot" then we need to update
if (q <= dot)
dot += ch;
- // file_modified++;
+ // modified_count++;
}
} else if (strncmp(cmd, "rewind", i) == 0) { // rewind cmd line args
- if (file_modified && !useforce) {
+ if (modified_count && !useforce) {
status_line_bold("No write since last change (:%s! overrides)", cmd);
} else {
// reset the filenames to edit
@@ -1438,8 +1442,8 @@ static void colon(char *buf)
} else {
status_line("'%s' %dL, %dC", fn, li, l);
if (q == text && r == end - 1 && l == ch) {
- file_modified = 0;
- last_file_modified = -1;
+ modified_count = 0;
+ last_modified_count = -1;
}
if ((cmd[0] == 'x' || cmd[1] == 'q' || cmd[1] == 'n'
|| cmd[0] == 'X' || cmd[1] == 'Q' || cmd[1] == 'N'
@@ -1940,7 +1944,7 @@ static char *char_insert(char *p, char c, int undo) // insert the char c at 'p'
# endif
}
#else
- file_modified++;
+ modified_count++;
#endif /* ENABLE_FEATURE_VI_UNDO */
p++;
} else if (c == 27) { // Is this an ESC?
@@ -1988,7 +1992,7 @@ static char *char_insert(char *p, char c, int undo) // insert the char c at 'p'
# endif
}
#else
- file_modified++;
+ modified_count++;
#endif /* ENABLE_FEATURE_VI_UNDO */
p += 1 + stupid_insert(p, c); // insert the char
#if ENABLE_FEATURE_VI_SETOPTS
@@ -2206,8 +2210,19 @@ static void showmatching(char *p)
#endif /* FEATURE_VI_SETOPTS */
#if ENABLE_FEATURE_VI_UNDO
+static void flush_undo_data(void)
+{
+ struct undo_object *undo_entry;
+
+ while (undo_stack_tail) {
+ undo_entry = undo_stack_tail;
+ undo_stack_tail = undo_entry->prev;
+ free(undo_entry);
+ }
+}
+
// Undo functions and hooks added by Jody Bruchon (jody at jodybruchon.com)
-static void undo_push(char *src, unsigned int length, unsigned char u_type) // Add to the undo stack
+static void undo_push(char *src, unsigned int length, uint8_t u_type) // Add to the undo stack
{
struct undo_object *undo_entry;
@@ -2275,10 +2290,19 @@ static void undo_push(char *src, unsigned int length, unsigned char u_type) // A
u_type = u_type & ~UNDO_QUEUED_FLAG;
#endif
- // Allocate a new undo object and use it as the stack tail
- undo_entry = xzalloc(sizeof(*undo_entry));
- undo_entry->prev = undo_stack_tail;
- undo_stack_tail = undo_entry;
+ // Allocate a new undo object
+ if (u_type == UNDO_DEL || u_type == UNDO_DEL_CHAIN) {
+ // For UNDO_DEL objects, save deleted text
+ if ((src + length) == end)
+ length--;
+ // If this deletion empties text[], strip the newline. When the buffer becomes
+ // zero-length, a newline is added back, which requires this to compensate.
+ undo_entry = xzalloc(offsetof(struct undo_object, undo_text) + length);
+ memcpy(undo_entry->undo_text, src, length);
+ } else {
+ undo_entry = xzalloc(sizeof(*undo_entry));
+ }
+ undo_entry->length = length;
#if ENABLE_FEATURE_VI_UNDO_QUEUE
if ((u_type & UNDO_USE_SPOS) != 0) {
undo_entry->start = undo_queue_spos - text; // use start position from queue
@@ -2289,18 +2313,12 @@ static void undo_push(char *src, unsigned int length, unsigned char u_type) // A
#else
undo_entry->start = src - text;
#endif
- // For UNDO_DEL objects, copy the deleted text somewhere
undo_entry->u_type = u_type;
- if (u_type == UNDO_DEL || u_type == UNDO_DEL_CHAIN) {
- if ((src + length) == end)
- length--;
- // If this deletion empties text[], strip the newline. When the buffer becomes
- // zero-length, a newline is added back, which requires this to compensate.
- undo_entry->undo_text = xmalloc(length);
- memcpy(undo_entry->undo_text, src, length);
- }
- undo_entry->length = length;
- file_modified++;
+
+ // Push it on undo stack
+ undo_entry->prev = undo_stack_tail;
+ undo_stack_tail = undo_entry;
+ modified_count++;
}
static void undo_pop(void) // Undo the last operation
@@ -2326,9 +2344,8 @@ static void undo_pop(void) // Undo the last operation
u_start = text + undo_entry->start;
text_hole_make(u_start, undo_entry->length);
memcpy(u_start, undo_entry->undo_text, undo_entry->length);
- free(undo_entry->undo_text);
status_line("Undo [%d] %s %d chars at position %d",
- file_modified, "restored",
+ modified_count, "restored",
undo_entry->length, undo_entry->start
);
break;
@@ -2339,7 +2356,7 @@ static void undo_pop(void) // Undo the last operation
u_end = u_start - 1 + undo_entry->length;
text_hole_delete(u_start, u_end, NO_UNDO);
status_line("Undo [%d] %s %d chars at position %d",
- file_modified, "deleted",
+ modified_count, "deleted",
undo_entry->length, undo_entry->start
);
break;
@@ -2360,7 +2377,7 @@ static void undo_pop(void) // Undo the last operation
// Deallocate the undo object we just processed
undo_stack_tail = undo_entry->prev;
free(undo_entry);
- file_modified--;
+ modified_count--;
// For chained operations, continue popping all the way down the chain.
if (repeat) {
undo_pop(); // Follow the undo chain if one exists
@@ -2452,13 +2469,13 @@ static char *text_hole_delete(char *p, char *q, int undo) // delete "p" through
break;
# endif
}
- file_modified--;
+ modified_count--;
#endif
if (src < text || src > end)
goto thd0;
if (dest < text || dest >= end)
goto thd0;
- file_modified++;
+ modified_count++;
if (src >= end)
goto thd_atend; // just delete the end of the buffer
memmove(dest, src, cnt);
@@ -2885,7 +2902,7 @@ static int file_insert(const char *fn, char *p, int update_ro_status)
status_line_bold("can't read '%s'", fn);
}
// if (cnt >= size)
-// file_modified++;
+// modified_count++;
close(fd);
fi0:
#if ENABLE_FEATURE_VI_READONLY
@@ -2922,7 +2939,7 @@ static int file_write(char *fn, char *first, char *last)
ftruncate(fd, charcnt);
if (charcnt == cnt) {
// good write
- //file_modified = FALSE;
+ //modified_count = FALSE;
} else {
charcnt = 0;
}
@@ -3144,7 +3161,7 @@ static int format_edit_status(void)
int cur, percent, ret, trunc_at;
- // file_modified is now a counter rather than a flag. this
+ // modified_count is now a counter rather than a flag. this
// helps reduce the amount of line counting we need to do.
// (this will cause a mis-reporting of modified status
// once every MAXINT editing operations.)
@@ -3154,11 +3171,12 @@ static int format_edit_status(void)
// we're on, then we shouldn't have to do this count_lines()
cur = count_lines(text, dot);
- // reduce counting -- the total lines can't have
- // changed if we haven't done any edits.
- if (file_modified != last_file_modified) {
+ // count_lines() is expensive.
+ // Call it only if something was changed since last time
+ // we were here:
+ if (modified_count != last_modified_count) {
tot = cur + count_lines(dot, end - 1) - 1;
- last_file_modified = file_modified;
+ last_modified_count = modified_count;
}
// current line percent
@@ -3185,7 +3203,7 @@ static int format_edit_status(void)
#if ENABLE_FEATURE_VI_READONLY
(readonly_mode ? " [Readonly]" : ""),
#endif
- (file_modified ? " [Modified]" : ""),
+ (modified_count ? " [Modified]" : ""),
cur, tot, percent);
if (ret >= 0 && ret < trunc_at)
@@ -3814,7 +3832,7 @@ static void do_cmd(int c)
if (strncmp(p, "quit", cnt) == 0
|| strncmp(p, "q!", cnt) == 0 // delete lines
) {
- if (file_modified && p[1] != '!') {
+ if (modified_count && p[1] != '!') {
status_line_bold("No write since last change (:%s! overrides)", p);
} else {
editing = 0;
@@ -3829,8 +3847,8 @@ static void do_cmd(int c)
if (cnt == -1)
status_line_bold("Write error: %s", strerror(errno));
} else {
- file_modified = 0;
- last_file_modified = -1;
+ modified_count = 0;
+ last_modified_count = -1;
status_line("'%s' %dL, %dC", current_filename, count_lines(text, end - 1), cnt);
if (p[0] == 'x' || p[1] == 'q' || p[1] == 'n'
|| p[0] == 'X' || p[1] == 'Q' || p[1] == 'N'
@@ -3963,7 +3981,7 @@ static void do_cmd(int c)
undo_push((dot - 1), 1, UNDO_INS_CHAIN);
#else
*dot++ = ' ';
- file_modified++;
+ modified_count++;
#endif
while (isblank(*dot)) { // delete leading WS
text_hole_delete(dot, dot, ALLOW_UNDO_CHAIN);
@@ -4035,7 +4053,7 @@ static void do_cmd(int c)
indicate_error(c);
break;
}
- if (file_modified) {
+ if (modified_count) {
if (ENABLE_FEATURE_VI_READONLY && readonly_mode) {
status_line_bold("'%s' is read only", current_filename);
break;
@@ -4172,7 +4190,7 @@ static void do_cmd(int c)
undo_push(dot, 1, UNDO_INS_CHAIN);
#else
*dot = c1;
- file_modified++;
+ modified_count++;
#endif
}
end_cmd_q(); // stop adding to q
@@ -4226,10 +4244,10 @@ static void do_cmd(int c)
#else
if (islower(*dot)) {
*dot = toupper(*dot);
- file_modified++;
+ modified_count++;
} else if (isupper(*dot)) {
*dot = tolower(*dot);
- file_modified++;
+ modified_count++;
}
#endif
dot_right();
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