From 9ff230c3751957ce57a2ffbcf7a5d7667fa3d56c Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ingo=20B=C3=BCrk?= Date: Wed, 18 Feb 2015 20:01:32 +0100 Subject: [PATCH 1/4] remove unused statusline_buffer --- i3bar/include/common.h | 1 - i3bar/src/child.c | 4 ---- i3bar/src/main.c | 2 -- 3 files changed, 7 deletions(-) diff --git a/i3bar/include/common.h b/i3bar/include/common.h index e8b6be0a..90b11f78 100644 --- a/i3bar/include/common.h +++ b/i3bar/include/common.h @@ -17,7 +17,6 @@ typedef struct rect_t rect; struct ev_loop *main_loop; char *statusline; -char *statusline_buffer; struct rect_t { int x; diff --git a/i3bar/src/child.c b/i3bar/src/child.c index d0f0c5fb..c0ea3613 100644 --- a/i3bar/src/child.c +++ b/i3bar/src/child.c @@ -56,7 +56,6 @@ parser_ctx parser_context; /* The buffer statusline points to */ struct statusline_head statusline_head = TAILQ_HEAD_INITIALIZER(statusline_head); -char *statusline_buffer = NULL; int child_stdin; @@ -115,9 +114,6 @@ void cleanup(void) { if (stdin_io != NULL) { ev_io_stop(main_loop, stdin_io); FREE(stdin_io); - FREE(statusline_buffer); - /* statusline pointed to memory within statusline_buffer */ - statusline = NULL; } if (child_sig != NULL) { diff --git a/i3bar/src/main.c b/i3bar/src/main.c index 371aeec9..ee3d81b9 100644 --- a/i3bar/src/main.c +++ b/i3bar/src/main.c @@ -171,8 +171,6 @@ int main(int argc, char **argv) { kill_child(); - FREE(statusline_buffer); - clean_xcb(); ev_default_destroy(); From 296fbdde125a1fb76814eedd5c632b1cecb729f9 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ingo=20B=C3=BCrk?= Date: Wed, 18 Feb 2015 20:11:42 +0100 Subject: [PATCH 2/4] Introduce a statusline buffer. A buffer is introduced for the statusline which will only be copied to the actual statusline once an entire statusline is parsed. This avoids a race condition where incompletely parsed statuslines were rendered, causing only some status blocks to be rendered which is visible to the user as a flickering. fixes #1480 --- i3bar/src/child.c | 63 ++++++++++++++++++++++++++++++----------------- 1 file changed, 41 insertions(+), 22 deletions(-) diff --git a/i3bar/src/child.c b/i3bar/src/child.c index c0ea3613..1860b879 100644 --- a/i3bar/src/child.c +++ b/i3bar/src/child.c @@ -54,25 +54,40 @@ typedef struct parser_ctx { parser_ctx parser_context; -/* The buffer statusline points to */ struct statusline_head statusline_head = TAILQ_HEAD_INITIALIZER(statusline_head); +/* Used temporarily while reading a statusline */ +struct statusline_head statusline_buffer = TAILQ_HEAD_INITIALIZER(statusline_buffer); int child_stdin; /* - * Clears all blocks from the statusline structure in memory and frees their - * associated resources. + * Remove all blocks from the given statusline. + * If free_resources is set, the fields of each status block will be free'd. */ -static void clear_status_blocks() { +static void clear_statusline(struct statusline_head *head, bool free_resources) { struct status_block *first; - while (!TAILQ_EMPTY(&statusline_head)) { - first = TAILQ_FIRST(&statusline_head); - I3STRING_FREE(first->full_text); - TAILQ_REMOVE(&statusline_head, first, blocks); + while (!TAILQ_EMPTY(head)) { + first = TAILQ_FIRST(head); + if (free_resources) { + I3STRING_FREE(first->full_text); + FREE(first->color); + FREE(first->name); + } + + TAILQ_REMOVE(head, first, blocks); free(first); } } +static void copy_statusline(struct statusline_head *from, struct statusline_head *to) { + struct status_block *current; + TAILQ_FOREACH (current, from, blocks) { + struct status_block *new_block = smalloc(sizeof(struct status_block)); + memcpy(new_block, current, sizeof(struct status_block)); + TAILQ_INSERT_TAIL(to, new_block, blocks); + } +} + /* * Replaces the statusline in memory with an error message. Pass a format * string and format parameters as you would in `printf'. The next time @@ -80,7 +95,7 @@ static void clear_status_blocks() { * the space allocated for the statusline. */ __attribute__((format(printf, 1, 2))) static void set_statusline_error(const char *format, ...) { - clear_status_blocks(); + clear_statusline(&statusline_head, true); char *message; va_list args; @@ -126,20 +141,12 @@ void cleanup(void) { /* * The start of a new array is the start of a new status line, so we clear all - * previous entries. - * + * previous entries from the buffer. */ static int stdin_start_array(void *context) { - struct status_block *first; - while (!TAILQ_EMPTY(&statusline_head)) { - first = TAILQ_FIRST(&statusline_head); - I3STRING_FREE(first->full_text); - FREE(first->color); - FREE(first->name); - FREE(first->instance); - TAILQ_REMOVE(&statusline_head, first, blocks); - free(first); - } + // the blocks are still used by statusline_head, so we won't free the + // resources here. + clear_statusline(&statusline_buffer, false); return 1; } @@ -222,6 +229,10 @@ static int stdin_integer(void *context, long long val) { return 1; } +/* + * When a map is finished, we have an entire status block. + * Move it from the parser's context to the statusline buffer. + */ static int stdin_end_map(void *context) { parser_ctx *ctx = context; struct status_block *new_block = smalloc(sizeof(struct status_block)); @@ -232,11 +243,19 @@ static int stdin_end_map(void *context) { new_block->full_text = i3string_from_utf8("SPEC VIOLATION: full_text is NULL!"); if (new_block->urgent) ctx->has_urgent = true; - TAILQ_INSERT_TAIL(&statusline_head, new_block, blocks); + TAILQ_INSERT_TAIL(&statusline_buffer, new_block, blocks); return 1; } +/* + * When an array is finished, we have an entire statusline. + * Copy it from the buffer to the actual statusline. + */ static int stdin_end_array(void *context) { + DLOG("copying statusline_buffer to statusline_head\n"); + clear_statusline(&statusline_head, true); + copy_statusline(&statusline_buffer, &statusline_head); + DLOG("dumping statusline:\n"); struct status_block *current; TAILQ_FOREACH(current, &statusline_head, blocks) { From 1fde82d584fe5c341ac0bc6022032cd185dec393 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ingo=20B=C3=BCrk?= Date: Wed, 18 Feb 2015 20:23:26 +0100 Subject: [PATCH 3/4] removed forgotten declaration of unused variable --- i3bar/include/common.h | 1 - 1 file changed, 1 deletion(-) diff --git a/i3bar/include/common.h b/i3bar/include/common.h index 90b11f78..997a429e 100644 --- a/i3bar/include/common.h +++ b/i3bar/include/common.h @@ -16,7 +16,6 @@ typedef struct rect_t rect; struct ev_loop *main_loop; -char *statusline; struct rect_t { int x; From 801dd06c6da842e5e390132f549cd5dcc601e1c0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ingo=20B=C3=BCrk?= Date: Wed, 18 Feb 2015 20:29:11 +0100 Subject: [PATCH 4/4] free block->instance when cleaning up statusline --- i3bar/src/child.c | 1 + 1 file changed, 1 insertion(+) diff --git a/i3bar/src/child.c b/i3bar/src/child.c index 1860b879..6d2f58b9 100644 --- a/i3bar/src/child.c +++ b/i3bar/src/child.c @@ -72,6 +72,7 @@ static void clear_statusline(struct statusline_head *head, bool free_resources) I3STRING_FREE(first->full_text); FREE(first->color); FREE(first->name); + FREE(first->instance); } TAILQ_REMOVE(head, first, blocks);