Be stricter about const char*, Wwrite-strings will warn in the future and we don't want to try to overwrite string literals

16 files changed, 44 insertions, 33 deletions

diff --git a/Makefile b/Makefile
index 55be5ba..00a9f93 100644
--- a/Makefile
+++ b/Makefile
@@ -64,7 +64,7 @@ GIT_VERSION=`sh -c 'command -v git >/dev/null && test -d .git && git rev-parse H
 OPTS_debug=-D_DEBUG -g -ggdb # -pg -fprofile-arcs -ftest-coverage
 OPTS_production=-O3
 
-CFLAGS+=-I$(LIBOWFAT_HEADERS) -DGIT_VERSION=$(GIT_VERSION) -Wall -pipe -pthread -Wextra #-ansi -pedantic
+CFLAGS+=-I$(LIBOWFAT_HEADERS) -DGIT_VERSION=$(GIT_VERSION) -Wall -pipe -pthread -Wextra -Wwrite-strings #-ansi -pedantic
 LDFLAGS+=-L$(LIBOWFAT_LIBRARY) -lowfat -pthread
 
 BINARY =opentracker
@@ -119,8 +119,8 @@ $(OBJECTS_proxy_debug): $(HEADERS)
 # has to. tests/stubs.c supplies the few symbols those modules reference but
 # the tests never reach.
 TESTBIN=tests/runner
-TEST_SOURCES=tests/runner.c tests/test.c tests/stubs.c tests/t_scan_urlencoded_query.c tests/t_iovec.c tests/t_vector.c tests/t_random.c tests/t_hex.c tests/t_accesslist.c tests/t_scan.c tests/t_buf.c tests/t_ip.c tests/t_socket.c
-TEST_UNITS=scan_urlencoded_query.c ot_buf.c ot_ip.c ot_socket.c ot_iovec.c ot_vector.c ot_random.c ot_hex.c ot_scan.c ot_accesslist.c
+TEST_SOURCES=tests/runner.c tests/test.c tests/stubs.c tests/t_scan_urlencoded_query.c tests/t_iovec.c tests/t_vector.c tests/t_random.c tests/t_hex.c tests/t_accesslist.c tests/t_scan.c tests/t_buf.c tests/t_ip.c tests/t_socket.c tests/t_mutex.c
+TEST_UNITS=scan_urlencoded_query.c ot_buf.c ot_ip.c ot_socket.c ot_iovec.c ot_vector.c ot_random.c ot_hex.c ot_scan.c ot_accesslist.c ot_mutex.c
 TEST_HEADERS=tests/test.h $(HEADERS)
 # Tests reach code that sits behind feature flags, so the units under test are
 # built with those features enabled. A test binary is not a production binary.
diff --git a/opentracker.c b/opentracker.c
index 0af0d17..96a265a 100644
--- a/opentracker.c
+++ b/opentracker.c
@@ -305,7 +305,7 @@ static void listen_bind_one(ot_listen *entry) {
 
 #ifdef _DEBUG
   {
-    char *protos[] = {"TCP", "UDP", "UDP mcast"};
+    const char *protos[] = {"TCP", "UDP", "UDP mcast"};
     char  _debug[512];
     int   off  = snprintf(_debug, sizeof(_debug), "Binding socket type %s to address [", protos[entry->proto]);
     off       += ip_format(_debug + off, entry->ip);
diff --git a/ot_accesslist.c b/ot_accesslist.c
index 2465ada..d7e88ee 100644
--- a/ot_accesslist.c
+++ b/ot_accesslist.c
@@ -32,10 +32,10 @@
 
 /* GLOBAL VARIABLES */
 #ifdef WANT_ACCESSLIST
-char *g_accesslist_filename = NULL;
+const char *g_accesslist_filename = NULL;
 #ifdef WANT_DYNAMIC_ACCESSLIST
-char *g_accesslist_pipe_add    = NULL;
-char *g_accesslist_pipe_delete = NULL;
+const char *g_accesslist_pipe_add    = NULL;
+const char *g_accesslist_pipe_delete = NULL;
 #endif
 static pthread_mutex_t g_accesslist_mutex;
 
@@ -272,7 +272,7 @@ static void *accesslist_worker(void *args) {
 
 #ifdef WANT_DYNAMIC_ACCESSLIST
 static pthread_t thread_adder_id, thread_deleter_id;
-static void     *accesslist_adddel_worker(char *fifoname, ot_accesslist *_Atomic *adding_to, ot_accesslist *_Atomic *removing_from) {
+static void     *accesslist_adddel_worker(const char *fifoname, ot_accesslist *_Atomic *adding_to, ot_accesslist *_Atomic *removing_from) {
   struct stat st;
 
   if (!stat(fifoname, &st)) {
diff --git a/ot_accesslist.h b/ot_accesslist.h
index 30aaebd..9dfdd95 100644
--- a/ot_accesslist.h
+++ b/ot_accesslist.h
@@ -23,10 +23,10 @@ void         accesslist_cleanup(void);
    line, and return how many were written to dest */
 size_t       accesslist_parse_hashes(ot_hash *dest, size_t capacity, const char *buf, size_t len);
 
-extern char *g_accesslist_filename;
+extern const char *g_accesslist_filename;
 #ifdef WANT_DYNAMIC_ACCESSLIST
-extern char *g_accesslist_pipe_add;
-extern char *g_accesslist_pipe_delete;
+extern const char *g_accesslist_pipe_add;
+extern const char *g_accesslist_pipe_delete;
 #endif
 
 #else
diff --git a/ot_config.c b/ot_config.c
index 43c07c5..e9666f9 100644
--- a/ot_config.c
+++ b/ot_config.c
@@ -22,10 +22,10 @@
 #include "ot_stats.h"
 #include "trackerlogic.h"
 
-char         *g_redirecturl;
-char         *g_serverdir;
-char         *g_serveruser;
-char         *g_statefile;
+const char   *g_redirecturl;
+const char   *g_serverdir;
+const char   *g_serveruser;
+const char   *g_statefile;
 
 #define OT_LISTEN_INHERIT (-1)
 
@@ -122,13 +122,13 @@ static int listen_scan_options(char *p, int *shared, int *workers) {
 }
 
 
-char *set_config_option(char **option, char *value) {
+static const char *set_config_option(const char **option, char *value) {
 #ifdef _DEBUG
   fprintf(stderr, "Setting config option: %s\n", value);
 #endif
   while (isspace(*value))
     ++value;
-  free(*option);
+  free((char *)*option);
   return *option = strdup(value);
 }
 
diff --git a/ot_config.h b/ot_config.h
index ab25e2c..059573a 100644
--- a/ot_config.h
+++ b/ot_config.h
@@ -22,10 +22,10 @@ typedef struct {
   int64_t    sock;
 } ot_listen;
 
-extern char *g_redirecturl;
-extern char *g_serverdir;
-extern char *g_serveruser;
-extern char *g_statefile;
+extern const char *g_redirecturl;
+extern const char *g_serverdir;
+extern const char *g_serveruser;
+extern const char *g_statefile;
 
 /* Reads the command line and every config file it names. Exits on error. */
 void       config_parse(int argc, char **argv);
diff --git a/ot_http.c b/ot_http.c
index 6448860..fc27eb8 100644
--- a/ot_http.c
+++ b/ot_http.c
@@ -37,9 +37,9 @@
 
 #define OT_MAXMULTISCRAPE_COUNT 64
 #define OT_BATCH_LIMIT          (1024 * 1024 * 16)
-extern char *g_redirecturl;
+extern const char *g_redirecturl;
 
-char        *g_stats_path;
+const char  *g_stats_path;
 ssize_t      g_stats_path_len;
 
 enum { SUCCESS_HTTP_HEADER_LENGTH = 80, SUCCESS_HTTP_SIZE_OFF = 17 };
@@ -125,9 +125,9 @@ static void http_senddata(const int64_t sock, struct ot_workstruct *ws) {
 #define HTTPERROR_404            return http_issue_error(sock, ws, CODE_HTTPERROR_404)
 #define HTTPERROR_500            return http_issue_error(sock, ws, CODE_HTTPERROR_500)
 ssize_t http_issue_error(const int64_t sock, struct ot_workstruct *ws, int code) {
-  char *error_code[] = {"302 Found",      "400 Invalid Request", "400 Invalid Request", "400 Invalid Request",      "402 Payment Required",
+  const char *error_code[] = {"302 Found",      "400 Invalid Request", "400 Invalid Request", "400 Invalid Request",      "402 Payment Required",
                         "403 Not Modest", "403 Access Denied",   "404 Not Found",       "500 Internal Server Error"};
-  char *title        = error_code[code];
+  const char *title  = error_code[code];
 
   ws->reply          = ws->outbuf;
   if (code == CODE_HTTPERROR_302)
@@ -491,7 +491,7 @@ unsigned long long numwants[201];
 #endif
 
 #if defined(WANT_KEEPALIVE) || defined(WANT_IP_FROM_PROXY)
-static char *http_header(char *data, size_t byte_count, char *header) {
+static char *http_header(char *data, size_t byte_count, const char *header) {
   size_t i;
   long   sl = strlen(header);
   for (i = 0; i + sl + 2 < byte_count; ++i) {
diff --git a/ot_http.h b/ot_http.h
index 965820f..abad83a 100644
--- a/ot_http.h
+++ b/ot_http.h
@@ -37,7 +37,7 @@ ssize_t        http_handle_request(const int64_t s, struct ot_workstruct *ws);
 ssize_t        http_sendiovecdata(const int64_t s, struct ot_workstruct *ws, size_t iovec_entries, struct iovec *iovector, int is_partial);
 ssize_t        http_issue_error(const int64_t s, struct ot_workstruct *ws, int code);
 
-extern char   *g_stats_path;
+extern const char *g_stats_path;
 extern ssize_t g_stats_path_len;
 
 #endif
diff --git a/ot_stats.c b/ot_stats.c
index f938e91..6589aef 100644
--- a/ot_stats.c
+++ b/ot_stats.c
@@ -53,7 +53,7 @@ static unsigned long long ot_full_scrape_count;
 static unsigned long long ot_full_scrape_request_count;
 static unsigned long long ot_full_scrape_size;
 static unsigned long long ot_failed_request_counts[CODE_HTTPERROR_COUNT];
-static char              *ot_failed_request_names[] = {
+static const char        *ot_failed_request_names[] = {
     "302 Redirect", "400 Parse Error", "400 Invalid Parameter", "400 Invalid Parameter (compact=0)", "400 Not Modest",
     "402 Payment Required", "403 Access Denied", "404 Not found", "500 Internal Server Error"};
 static unsigned long long ot_renewed[OT_PEER_TIMEOUT];
diff --git a/proxy.c b/proxy.c
index a870c63..219d926 100644
--- a/proxy.c
+++ b/proxy.c
@@ -72,7 +72,7 @@ static void *livesync_worker(void *args);
 static void *streamsync_worker(void *args);
 static void livesync_proxytell(uint8_t prefix, uint8_t *info_hash, uint8_t *peer);
 
-void exerr(char *message) {
+void exerr(const char *message) {
   fprintf(stderr, "%s\n", message);
   exit(111);
 }
diff --git a/scan_urlencoded_query.h b/scan_urlencoded_query.h
index d0929cf..f71752d 100644
--- a/scan_urlencoded_query.h
+++ b/scan_urlencoded_query.h
@@ -11,8 +11,8 @@
 #include <sys/types.h>
 
 typedef struct {
-  char *key;
-  int   value;
+  const char *key;
+  int         value;
 } ot_keywords;
 
 typedef enum {
diff --git a/tests/runner.c b/tests/runner.c
index db62246..972a56a 100644
--- a/tests/runner.c
+++ b/tests/runner.c
@@ -23,6 +23,7 @@ static const struct module modules[] = {{"scan_urlencoded_query", test_scan_urle
                                         {"ot_buf", test_buf},
                                         {"ot_ip", test_ip},
                                         {"ot_socket", test_socket},
+                                        {"ot_mutex", test_mutex},
                                         {"ot_accesslist", test_accesslist},
                                         {NULL, NULL}};
 
diff --git a/tests/stubs.c b/tests/stubs.c
index ce93071..09a7312 100644
--- a/tests/stubs.c
+++ b/tests/stubs.c
@@ -18,3 +18,12 @@ void free_peerlist(ot_peerlist *peer_list) { (void)peer_list; }
    neither of which any test drives. */
 time_t       g_now_seconds;
 volatile int g_opentracker_running;
+
+/* ot_mutex.c wakes the main loop through the self pipe when a result is
+   ready. The queue tests never get that far. */
+int  g_self_pipe[2] = {-1, -1};
+long io_trywrite(long d, const char *buf, long len) {
+  (void)d;
+  (void)buf;
+  return len;
+}
diff --git a/tests/test.h b/tests/test.h
index d79c4d2..9677524 100644
--- a/tests/test.h
+++ b/tests/test.h
@@ -86,5 +86,6 @@ void test_scan(void);
 void test_buf(void);
 void test_ip(void);
 void test_socket(void);
+void test_mutex(void);
 
 #endif
diff --git a/trackerlogic.c b/trackerlogic.c
index 52c8c18..0fa7bfb 100644
--- a/trackerlogic.c
+++ b/trackerlogic.c
@@ -550,7 +550,7 @@ void trackerlogic_add_random_torrents(size_t amount) {
 }
 #endif
 
-void exerr(char *message) {
+void exerr(const char *message) {
   fprintf(stderr, "%s\n", message);
   exit(111);
 }
diff --git a/trackerlogic.h b/trackerlogic.h
index aa10a54..42018c3 100644
--- a/trackerlogic.h
+++ b/trackerlogic.h
@@ -181,7 +181,7 @@ struct ot_workstruct {
 
 void   trackerlogic_init(void);
 void   trackerlogic_deinit(void);
-void   exerr(char *message);
+void   exerr(const char *message);
 
 /* add_peer_to_torrent does only release the torrent bucket if from_sync is set,
    otherwise it is released in return_peers_for_torrent */