func_strings: Add trim functions.

Adds TRIM, LTRIM, and RTRIM, which can be used
for trimming leading and trailing whitespace
from strings.

ASTERISK-30222 #close

Change-Id: I50fb0c40726d044a7a41939fa9026f3da4872554

diff --git a/doc/CHANGES-staging/func_strings_trim.txt b/doc/CHANGES-staging/func_strings_trim.txt
new file mode 100644 (file)
index 0000000..ade7a4b
--- /dev/null
+++ b/doc/CHANGES-staging/func_strings_trim.txt
@@ -0,0 +1,5 @@
+Subject: func_strings
+
+Three new functions, TRIM, LTRIM, and RTRIM, are
+now available for trimming leading and trailing
+whitespace.

diff --git a/funcs/func_strings.c b/funcs/func_strings.c
index 77cdc99f286d161481af47e5fefd946f3997998d..598e6a47b2586551d35557000d948006fbeb610f 100644 (file)
--- a/funcs/func_strings.c
+++ b/funcs/func_strings.c
@@ -4,7 +4,7 @@
  * Copyright (C) 2005-2006, Digium, Inc.
  * Portions Copyright (C) 2005, Tilghman Lesher.  All rights reserved.
  * Portions Copyright (C) 2005, Anthony Minessale II
- * Portions Copyright (C) 2021, Naveen Albert
+ * Portions Copyright (C) 2021, 2022, Naveen Albert
  *
  * See http://www.asterisk.org for more information about
  * the Asterisk project. Please do not directly contact
@@ -183,6 +183,51 @@ AST_THREADSTORAGE(tmp_buf);
                        </example>
                </description>
        </function>
+       <function name="TRIM" language="en_US">
+               <synopsis>
+                       Trim leading and trailing whitespace in a string
+               </synopsis>
+               <syntax>
+                       <parameter name="string" required="true" />
+               </syntax>
+               <description>
+                       <para>Replaces all leading and trailing whitespace in the provided string.</para>
+               </description>
+               <see-also>
+                       <ref type="function">LTRIM</ref>
+                       <ref type="function">RTRIM</ref>
+               </see-also>
+       </function>
+       <function name="LTRIM" language="en_US">
+               <synopsis>
+                       Trim leading whitespace in a string
+               </synopsis>
+               <syntax>
+                       <parameter name="string" required="true" />
+               </syntax>
+               <description>
+                       <para>Replaces all leading whitespace in the provided string.</para>
+               </description>
+               <see-also>
+                       <ref type="function">TRIM</ref>
+                       <ref type="function">RTRIM</ref>
+               </see-also>
+       </function>
+       <function name="RTRIM" language="en_US">
+               <synopsis>
+                       Trim trailing whitespace in a string
+               </synopsis>
+               <syntax>
+                       <parameter name="string" required="true" />
+               </syntax>
+               <description>
+                       <para>Replaces all trailing whitespace in the provided string.</para>
+               </description>
+               <see-also>
+                       <ref type="function">TRIM</ref>
+                       <ref type="function">LTRIM</ref>
+               </see-also>
+       </function>
        <function name="PASSTHRU" language="en_US">
                <synopsis>
                        Pass the given argument back as a value.
@@ -1045,6 +1090,84 @@ static struct ast_custom_function strbetween_function = {
        .read2 = strbetween,
 };
 
+#define ltrim(s) while (isspace(*s)) s++;
+#define rtrim(s) { \
+       if (s) { \
+               char *back = s + strlen(s); \
+               while (back != s && isspace(*--back)); \
+               if (*s) { \
+                       *(back + 1) = '\0'; \
+               } \
+       } \
+}
+
+static int function_trim(struct ast_channel *chan, const char *cmd, char *data, char *buf, size_t len)
+{
+       char *c;
+
+       if (ast_strlen_zero(data)) {
+               return -1;
+       }
+
+       c = ast_strdupa(data);
+       ltrim(c);
+       rtrim(c);
+
+       ast_copy_string(buf, c, len);
+
+       return 0;
+}
+
+static int function_ltrim(struct ast_channel *chan, const char *cmd, char *data, char *buf, size_t len)
+{
+       char *c;
+
+       if (ast_strlen_zero(data)) {
+               return -1;
+       }
+
+       c = data;
+       ltrim(c);
+
+       ast_copy_string(buf, c, len);
+
+       return 0;
+}
+
+static int function_rtrim(struct ast_channel *chan, const char *cmd, char *data, char *buf, size_t len)
+{
+       char *c;
+
+       if (ast_strlen_zero(data)) {
+               return -1;
+       }
+
+       c = ast_strdupa(data);
+       rtrim(c);
+
+       ast_copy_string(buf, c, len);
+
+       return 0;
+}
+
+#undef ltrim
+#undef rtrim
+
+static struct ast_custom_function trim_function = {
+       .name = "TRIM",
+       .read = function_trim,
+};
+
+static struct ast_custom_function ltrim_function = {
+       .name = "LTRIM",
+       .read = function_ltrim,
+};
+
+static struct ast_custom_function rtrim_function = {
+       .name = "RTRIM",
+       .read = function_rtrim,
+};
+
 static int regex(struct ast_channel *chan, const char *cmd, char *parse, char *buf,
                 size_t len)
 {
@@ -2126,6 +2249,59 @@ AST_TEST_DEFINE(test_STRBETWEEN)
 
        return res;
 }
+
+AST_TEST_DEFINE(test_TRIM)
+{
+       int i, res = AST_TEST_PASS;
+       struct ast_channel *chan; /* dummy channel */
+       struct ast_str *str; /* fancy string for holding comparing value */
+
+       const char *test_strings[][5] = {
+               {"TRIM", "  abcd ", "abcd"},
+               {"LTRIM", " abcd ", "abcd "},
+               {"RTRIM", " abcd ", " abcd"},
+               {"TRIM", "abcd", "abcd"},
+               {"TRIM", " a b c d ", "a b c d"},
+       };
+
+       switch (cmd) {
+       case TEST_INIT:
+               info->name = "func_TRIM";
+               info->category = "/funcs/func_strings/";
+               info->summary = "Test TRIM functions";
+               info->description = "Verify TRIM behavior";
+               return AST_TEST_NOT_RUN;
+       case TEST_EXECUTE:
+               break;
+       }
+
+       if (!(chan = ast_dummy_channel_alloc())) {
+               ast_test_status_update(test, "Unable to allocate dummy channel\n");
+               return AST_TEST_FAIL;
+       }
+
+       if (!(str = ast_str_create(64))) {
+               ast_test_status_update(test, "Unable to allocate dynamic string buffer\n");
+               ast_channel_release(chan);
+               return AST_TEST_FAIL;
+       }
+
+       for (i = 0; i < ARRAY_LEN(test_strings); i++) {
+               char tmp[512], tmp2[512] = "";
+
+               snprintf(tmp, sizeof(tmp), "${%s(%s)}", test_strings[i][0], test_strings[i][1]);
+               ast_str_substitute_variables(&str, 0, chan, tmp);
+               if (strcmp(test_strings[i][2], ast_str_buffer(str))) {
+                       ast_test_status_update(test, "Format string '%s' substituted to '%s'.  Expected '%s'.\n", test_strings[i][0], tmp2, test_strings[i][2]);
+                       res = AST_TEST_FAIL;
+               }
+       }
+
+       ast_free(str);
+       ast_channel_release(chan);
+
+       return res;
+}
 #endif
 
 static int unload_module(void)
@@ -2137,6 +2313,7 @@ static int unload_module(void)
        AST_TEST_UNREGISTER(test_FILTER);
        AST_TEST_UNREGISTER(test_STRREPLACE);
        AST_TEST_UNREGISTER(test_STRBETWEEN);
+       AST_TEST_UNREGISTER(test_TRIM);
        res |= ast_custom_function_unregister(&fieldqty_function);
        res |= ast_custom_function_unregister(&fieldnum_function);
        res |= ast_custom_function_unregister(&filter_function);
@@ -2163,6 +2340,9 @@ static int unload_module(void)
        res |= ast_custom_function_unregister(&push_function);
        res |= ast_custom_function_unregister(&unshift_function);
        res |= ast_custom_function_unregister(&passthru_function);
+       res |= ast_custom_function_unregister(&trim_function);
+       res |= ast_custom_function_unregister(&ltrim_function);
+       res |= ast_custom_function_unregister(&rtrim_function);
 
        return res;
 }
@@ -2176,6 +2356,7 @@ static int load_module(void)
        AST_TEST_REGISTER(test_FILTER);
        AST_TEST_REGISTER(test_STRREPLACE);
        AST_TEST_REGISTER(test_STRBETWEEN);
+       AST_TEST_REGISTER(test_TRIM);
        res |= ast_custom_function_register(&fieldqty_function);
        res |= ast_custom_function_register(&fieldnum_function);
        res |= ast_custom_function_register(&filter_function);
@@ -2202,6 +2383,9 @@ static int load_module(void)
        res |= ast_custom_function_register(&push_function);
        res |= ast_custom_function_register(&unshift_function);
        res |= ast_custom_function_register(&passthru_function);
+       res |= ast_custom_function_register(&trim_function);
+       res |= ast_custom_function_register(&ltrim_function);
+       res |= ast_custom_function_register(&rtrim_function);
 
        return res;
 }