MINOR: config: add predicates "streq()" and "strneq()" to conditional expressions

"streq(str1,str2)" will return true if the two strings match while
"strneq(str1,str2)" will return true only if they differ. This is
convenient to match an environment variable against a predefined value.

diff --git a/doc/configuration.txt b/doc/configuration.txt
index ff90526d868fcd653c7b3d050c7c4ab20d0a6696..4242e014e97f32349540c7970f224fbf271d210f 100644 (file)
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -814,6 +814,9 @@ The list of currently supported predicates is the following:
   - defined(<name>)       : returns true if an environment variable <name>
                             exists, regardless of its contents
 
+  - streq(<str1>,<str2>)  : returns true only if the two strings are equal
+  - strneq(<str1>,<str2>) : returns true only if the two strings differ
+
 Example:
 
    .if defined(HAPROXY_MWORKER)
@@ -822,6 +825,14 @@ Example:
           ...
    .endif
 
+   .if strneq("$SSL_ONLY",yes)
+          bind :80
+   .endif
+
+   .if streq("$WITH_SSL",yes)
+          bind :443 ssl crt ...
+   .endif
+
 Three other directives are provided to report some status:
 
   - .notice "message"  : emit this message at level NOTICE

diff --git a/src/cfgparse.c b/src/cfgparse.c
index d8ba76a8b460c442e1ff3f92959567d951292084..9daac06c2f027d74679285f965b34136e426142e 100644 (file)
--- a/src/cfgparse.c
+++ b/src/cfgparse.c
@@ -137,6 +137,8 @@ enum nested_cond_state {
 enum cond_predicate {
        CFG_PRED_NONE,            // none
        CFG_PRED_DEFINED,         // "defined"
+       CFG_PRED_STREQ,           // "streq"
+       CFG_PRED_STRNEQ,          // "strneq"
 };
 
 struct cond_pred_kw {
@@ -148,6 +150,8 @@ struct cond_pred_kw {
 /* supported condition predicates */
 const struct cond_pred_kw cond_predicates[] = {
        { "defined",          CFG_PRED_DEFINED,         ARG1(1, STR)         },
+       { "streq",            CFG_PRED_STREQ,           ARG2(2, STR, STR)    },
+       { "strneq",           CFG_PRED_STRNEQ,          ARG2(2, STR, STR)    },
        { NULL, CFG_PRED_NONE, 0 }
 };
 
@@ -1718,6 +1722,14 @@ static int cfg_eval_condition(char **args, char **err, const char **errptr)
                        ret = getenv(argp[0].data.str.area) != NULL;
                        goto done;
 
+               case CFG_PRED_STREQ:    // checks if the two arg are equal
+                       ret = strcmp(argp[0].data.str.area, argp[1].data.str.area) == 0;
+                       goto done;
+
+               case CFG_PRED_STRNEQ:   // checks if the two arg are different
+                       ret = strcmp(argp[0].data.str.area, argp[1].data.str.area) != 0;
+                       goto done;
+
                default:
                        memprintf(err, "internal error: unhandled conditional expression predicate '%s'", cond_pred->word);
                        if (errptr)