Add TR_TORRENT_LABELS to env variables available to scripts (#868)

* Add TR_TORRENT_LABELS to env variables available to scripts

* Add unit test for tr_strjoin

Co-authored-by: Charles Kerr <charles@charleskerr.com>

libtransmission/torrent.c

@@ -2253,6 +2253,8 @@ static void torrentCallScript(tr_torrent const* tor, char const* script)
         NULL
     };
 
+    char* labels = tr_strjoin((char const* const*)tr_ptrArrayBase(&tor->labels), tr_ptrArraySize(&tor->labels), ",");
+
     char* const env[] =
     {
         tr_strdup_printf("TR_APP_VERSION=%s", SHORT_VERSION_STRING),
@@ -2261,6 +2263,7 @@ static void torrentCallScript(tr_torrent const* tor, char const* script)
         tr_strdup_printf("TR_TORRENT_HASH=%s", tor->info.hashString),
         tr_strdup_printf("TR_TORRENT_ID=%d", tr_torrentId(tor)),
         tr_strdup_printf("TR_TORRENT_NAME=%s", tr_torrentName(tor)),
+        tr_strdup_printf("TR_TORRENT_LABELS=%s", labels),
         NULL
     };
 
@@ -2276,6 +2279,7 @@ static void torrentCallScript(tr_torrent const* tor, char const* script)
 
     tr_free_ptrv((void* const*)env);
     tr_free_ptrv((void* const*)cmd);
+    tr_free(labels);
     tr_free(torrent_dir);
 }
 

libtransmission/utils-test.c

@@ -80,6 +80,38 @@ static int test_strstrip(void)
     return 0;
 }
 
+static int test_strjoin(void)
+{
+    char* out;
+
+    char const* in1[] = { "one", "two" };
+    out = tr_strjoin(in1, 2, ", ");
+    check_str(out, ==, "one, two");
+    tr_free(out);
+
+    char const* in2[] = { "hello" };
+    out = tr_strjoin(in2, 1, "###");
+    check_str(out, ==, "hello");
+    tr_free(out);
+
+    char const* in3[] = { "a", "b", "ccc", "d", "eeeee" };
+    out = tr_strjoin(in3, 5, " ");
+    check_str(out, ==, "a b ccc d eeeee");
+    tr_free(out);
+
+    char const* in4[] = { "7", "ate", "9" };
+    out = tr_strjoin(in4, 3, "");
+    check_str(out, ==, "7ate9");
+    tr_free(out);
+
+    char const** in5;
+    out = tr_strjoin(in5, 0, "a");
+    check_str(out, ==, "");
+    tr_free(out);
+
+    return 0;
+}
+
 static int test_buildpath(void)
 {
     char* out;
@@ -545,6 +577,7 @@ int main(void)
         test_strip_positional_args,
         test_strdup_printf,
         test_strstrip,
+        test_strjoin,
         test_truncd,
         test_url,
         test_utf8,

libtransmission/utils.c

@@ -587,6 +587,37 @@ char* tr_strsep(char** str, char const* delims)
 #endif
 }
 
+char* tr_strjoin(char const* const* arr, size_t len, char const* delim)
+{
+    size_t total_len = 1;
+    size_t delim_len = strlen(delim);
+    for (size_t i = 0; i < len; ++i)
+    {
+        total_len += strlen(arr[i]);
+    }
+
+    total_len += len > 0 ? (len - 1) * delim_len : 0;
+
+    char* const ret = tr_new(char, total_len);
+    char* p = ret;
+
+    for (size_t i = 0; i < len; ++i)
+    {
+        if (i > 0)
+        {
+            memcpy(p, delim, delim_len);
+            p += delim_len;
+        }
+
+        size_t const part_len = strlen(arr[i]);
+        memcpy(p, arr[i], part_len);
+        p += part_len;
+    }
+
+    *p = '\0';
+    return ret;
+}
+
 char* tr_strstrip(char* str)
 {
     if (str != NULL)

libtransmission/utils.h

@@ -254,6 +254,9 @@ char const* tr_strcasestr(char const* haystack, char const* needle);
 /** @brief Portability wrapper for strsep() that uses the system implementation if available */
 char* tr_strsep(char** str, char const* delim);
 
+/** @brief Concatenates array of strings with delimiter in between elements */
+char* tr_strjoin(char const* const* arr, size_t len, char const* delim);
+
 /***
 ****
 ***/