Clean up the maximum-files-open check a little

CHANGELOG.md

@@ -1,3 +1,7 @@
+## 1.9.13
+
+* Don't trust the OS so much about how many files can be open
+
 ## 1.9.12
 
 * Limit the size of the parallel parsing streaming input buffer

geojson.c

@@ -147,31 +147,31 @@ void init_cpus() {
 	// Round down to a power of 2
 	CPUS = 1 << (int) (log(CPUS) / log(2));
 
-	TEMP_FILES = 64;
-	MAX_FILES = 64;
-
 	struct rlimit rl;
 	if (getrlimit(RLIMIT_NOFILE, &rl) != 0) {
 		perror("getrlimit");
+		exit(EXIT_FAILURE);
 	} else {
+		MAX_FILES = rl.rlim_cur;
+	}
+
+	// Don't really want too many temporary files, because the file system
+	// will start to bog down eventually
+	if (MAX_FILES > 2000) {
+		MAX_FILES = 2000;
+	}
+
 	// MacOS can run out of system file descriptors
 	// even if we stay under the rlimit, so try to
 	// find out the real limit.
-
-		long long fds[rl.rlim_cur];
+	long long fds[MAX_FILES];
 	long long i;
-		for (i = 0; i < rl.rlim_cur; i++) {
+	for (i = 0; i < MAX_FILES; i++) {
 		fds[i] = open("/dev/null", O_RDONLY);
 		if (fds[i] < 0) {
 			break;
 		}
 	}
-
-		MAX_FILES = i * 3 / 4;
-		if (MAX_FILES > 2000) {
-			MAX_FILES = 2000;
-		}
-
 	long long j;
 	for (j = 0; j < i; j++) {
 		if (close(fds[j]) < 0) {
@@ -180,12 +180,18 @@ void init_cpus() {
 		}
 	}
 
-		TEMP_FILES = MAX_FILES / 3;
+	// Scale down because we really don't want to run the system out of files
+	MAX_FILES = i * 3 / 4;
+	if (MAX_FILES < 32) {
+		fprintf(stderr, "Can't open a useful number of files: %lld\n", MAX_FILES);
+		exit(EXIT_FAILURE);
+	}
+
+	TEMP_FILES = (MAX_FILES - 10) / 2;
 	if (TEMP_FILES > CPUS * 4) {
 		TEMP_FILES = CPUS * 4;
 	}
 }
-}
 
 size_t fwrite_check(const void *ptr, size_t size, size_t nitems, FILE *stream, const char *fname) {
 	size_t w = fwrite(ptr, size, nitems, stream);

version.h

@@ -1 +1 @@
-#define VERSION "tippecanoe v1.9.12\n"
+#define VERSION "tippecanoe v1.9.13\n"