From 9c4caf49a2e65ca03efe67332493de28c177be14 Mon Sep 17 00:00:00 2001 From: nicm Date: Fri, 6 Oct 2017 18:02:30 +0000 Subject: [PATCH] Support %else in config files to match %if, from Brad Town in GitHub issue 1071. --- cfg.c | 172 +++++++++++++++++++++++++++++++++++++++++++++++---------- tmux.1 | 25 +++++++-- 2 files changed, 164 insertions(+), 33 deletions(-) diff --git a/cfg.c b/cfg.c index 5f5df24a..86901e6a 100644 --- a/cfg.c +++ b/cfg.c @@ -27,6 +27,17 @@ #include "tmux.h" +/* Condition for %if, %elif, %else and %endif. */ +struct cfg_cond { + size_t line; /* line number of %if */ + int met; /* condition was met */ + int skip; /* skip later %elif/%else */ + int saw_else; /* saw a %else */ + + TAILQ_ENTRY(cfg_cond) entry; +}; +TAILQ_HEAD(cfg_conds, cfg_cond); + static char *cfg_file; int cfg_finished; static char **cfg_causes; @@ -102,6 +113,124 @@ start_cfg(void) cmdq_append(NULL, cmdq_get_callback(cfg_done, NULL)); } +static int +cfg_check_condition(const char *path, size_t line, const char *p, int *skip) +{ + struct format_tree *ft; + char *s; + int result; + + while (isspace((u_char)*p)) + p++; + if (p[0] == '\0') { + cfg_add_cause("%s:%zu: invalid condition", path, line); + *skip = 1; + return (0); + } + + ft = format_create(NULL, NULL, FORMAT_NONE, FORMAT_NOJOBS); + s = format_expand(ft, p); + result = format_true(s); + free(s); + format_free(ft); + + *skip = result; + return (result); +} + +static void +cfg_handle_if(const char *path, size_t line, struct cfg_conds *conds, + const char *p) +{ + struct cfg_cond *cond; + struct cfg_cond *parent = TAILQ_FIRST(conds); + + /* + * Add a new condition. If a previous condition exists and isn't + * currently met, this new one also can't be met. + */ + cond = xcalloc(1, sizeof *cond); + cond->line = line; + if (parent == NULL || parent->met) + cond->met = cfg_check_condition(path, line, p, &cond->skip); + else + cond->skip = 1; + cond->saw_else = 0; + TAILQ_INSERT_HEAD(conds, cond, entry); +} + +static void +cfg_handle_elif(const char *path, size_t line, struct cfg_conds *conds, + const char *p) +{ + struct cfg_cond *cond = TAILQ_FIRST(conds); + + /* + * If a previous condition exists and wasn't met, check this + * one instead and change the state. + */ + if (cond == NULL || cond->saw_else) + cfg_add_cause("%s:%zu: unexpected %%elif", path, line); + else if (!cond->skip) + cond->met = cfg_check_condition(path, line, p, &cond->skip); + else + cond->met = 0; +} + +static void +cfg_handle_else(const char *path, size_t line, struct cfg_conds *conds) +{ + struct cfg_cond *cond = TAILQ_FIRST(conds); + + /* + * If a previous condition exists and wasn't met and wasn't already + * %else, use this one instead. + */ + if (cond == NULL || cond->saw_else) { + cfg_add_cause("%s:%zu: unexpected %%else", path, line); + return; + } + cond->saw_else = 1; + cond->met = !cond->skip; + cond->skip = 1; +} + +static void +cfg_handle_endif(const char *path, size_t line, struct cfg_conds *conds) +{ + struct cfg_cond *cond = TAILQ_FIRST(conds); + + /* + * Remove previous condition if one exists. + */ + if (cond == NULL) { + cfg_add_cause("%s:%zu: unexpected %%endif", path, line); + return; + } + TAILQ_REMOVE(conds, cond, entry); + free(cond); +} + +static void +cfg_handle_directive(const char *p, const char *path, size_t line, + struct cfg_conds *conds) +{ + int n = 0; + + while (p[n] != '\0' && !isspace((u_char)p[n])) + n++; + if (strncmp(p, "%if", n) == 0) + cfg_handle_if(path, line, conds, p + n); + else if (strncmp(p, "%elif", n) == 0) + cfg_handle_elif(path, line, conds, p + n); + else if (strcmp(p, "%else") == 0) + cfg_handle_else(path, line, conds); + else if (strcmp(p, "%endif") == 0) + cfg_handle_endif(path, line, conds); + else + cfg_add_cause("%s:%zu: invalid directive: %s", path, line, p); +} + int load_cfg(const char *path, struct client *c, struct cmdq_item *item, int quiet) { @@ -109,11 +238,13 @@ load_cfg(const char *path, struct client *c, struct cmdq_item *item, int quiet) const char delim[3] = { '\\', '\\', '\0' }; u_int found = 0; size_t line = 0; - char *buf, *cause1, *p, *q, *s; + char *buf, *cause1, *p, *q; struct cmd_list *cmdlist; struct cmdq_item *new_item; - int condition = 0; - struct format_tree *ft; + struct cfg_cond *cond, *cond1; + struct cfg_conds conds; + + TAILQ_INIT(&conds); log_debug("loading %s", path); if ((f = fopen(path, "rb")) == NULL) { @@ -137,33 +268,12 @@ load_cfg(const char *path, struct client *c, struct cmdq_item *item, int quiet) while (q != p && isspace((u_char)*q)) *q-- = '\0'; - if (condition != 0 && strcmp(p, "%endif") == 0) { - condition = 0; + if (*p == '%') { + cfg_handle_directive(p, path, line, &conds); continue; } - if (strncmp(p, "%if ", 4) == 0) { - if (condition != 0) { - cfg_add_cause("%s:%zu: nested %%if", path, - line); - continue; - } - ft = format_create(NULL, NULL, FORMAT_NONE, - FORMAT_NOJOBS); - - s = p + 3; - while (isspace((u_char)*s)) - s++; - s = format_expand(ft, s); - if (*s != '\0' && (s[0] != '0' || s[1] != '\0')) - condition = 1; - else - condition = -1; - free(s); - - format_free(ft); - continue; - } - if (condition == -1) + cond = TAILQ_FIRST(&conds); + if (cond != NULL && !cond->met) continue; cmdlist = cmd_string_parse(p, path, line, &cause1); @@ -190,6 +300,12 @@ load_cfg(const char *path, struct client *c, struct cmdq_item *item, int quiet) } fclose(f); + TAILQ_FOREACH_REVERSE_SAFE(cond, &conds, cfg_conds, entry, cond1) { + cfg_add_cause("%s:%zu: unterminated %%if", path, cond->line); + TAILQ_REMOVE(&conds, cond, entry); + free(cond); + } + return (found); } diff --git a/tmux.1 b/tmux.1 index 45eb83b2..218a16d2 100644 --- a/tmux.1 +++ b/tmux.1 @@ -976,22 +976,37 @@ them with and .Em %endif lines. +Additional +.Em %elif +and +.Em %else +lines may also be used. The argument to .Em %if -is expanded as a format and if it evaluates to false -(zero or empty), subsequent lines are ignored until +and +.Em %elif +is expanded as a format and if it evaluates to false (zero or empty), +subsequent lines are ignored until the next +.Em %elif , +.Em %else +or .Em %endif . For example: .Bd -literal -offset indent %if #{==:#{host},myhost} set -g status-style bg=red +%elif #{==:#{host},myotherhost} +set -g status-style bg=green +%else +set -g status-style bg=blue %endif .Ed .Pp Will change the status line to red if running on -.Ql myhost . -.Em %if -may not be nested. +.Ql myhost , +green if running on +.Ql myotherhost , +or blue if running on another host. .It Ic start-server .D1 (alias: Ic start ) Start the