Limit the number of extracts possible with osmium extract

So we don't run out of file descriptors. See #265.
osmcode · May 2, 2023 · 353e9d5 · frafra · May 18, 2023 · joto
1 parent 513e0de
commit 353e9d5
Show file tree

Hide file tree

Showing 2 changed files with 12 additions and 0 deletions.
diff --git a/man/osmium-extract.md b/man/osmium-extract.md
@@ -391,6 +391,12 @@ steps. First create several larger extracts and then split them again and
 again into smaller pieces.
 
 
+# LIMITS
+
+You can not have more than 500 extracts. Although chances are that you will be
+running out of memory long before that. See MEMORY USAGE.
+
+
 # EXAMPLES
 
 See the example config files in the *extract-example-config* directory. To

diff --git a/src/command_extract.cpp b/src/command_extract.cpp
@@ -72,6 +72,8 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 # include <unistd.h>
 #endif
 
+static constexpr const std::size_t max_extracts = 500;
+
 static osmium::Box parse_bbox(const rapidjson::Value& value) {
     if (value.IsArray()) {
         if (value.Size() != 4) {
@@ -622,6 +624,10 @@ bool CommandExtract::run() {
         throw config_error{"No extract specified in config file or on the command line."};
     }
 
+    if (m_extracts.size() > max_extracts) {
+        throw config_error{"Too many extracts specified in config file (Maximum: " + std::to_string(max_extracts) + ")."};
+    }
+
     show_extracts();
 
     m_strategy = make_strategy(m_strategy_name);