wget: add support for connect timeout

function                                             old     new   delta
open_socket                                           33      64     +31
wget_main                                           2182    2194     +12

Signed-off-by: Lauri Kasanen <curaga@operamail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

2 files changed, 30 insertions, 10 deletions

diff --git a/networking/Config.src b/networking/Config.src
index e1ae0c9d5..ca0ddcdd9 100644
--- a/networking/Config.src
+++ b/networking/Config.src
@@ -970,16 +970,18 @@ config FEATURE_WGET_LONG_OPTIONS
           Support long options for the wget applet.
 
 config FEATURE_WGET_TIMEOUT
-        bool "Enable read timeout option -T SEC"
+        bool "Enable timeout option -T SEC"
         default y
         depends on WGET
         help
-          Supports network read timeout for wget, so that wget will give
-          up and timeout when reading network data, through the -T command
-          line option.  Currently only network data read timeout is
-          supported (i.e., timeout is not applied to the DNS nor TCP
-          connection initialization).  When FEATURE_WGET_LONG_OPTIONS is
-          also enabled, the --timeout option will work in addition to -T.
+          Supports network read and connect timeouts for wget,
+          so that wget will give up and timeout, through the -T
+          command line option.
+
+          Currently only connect and network data read timeout are
+          supported (i.e., timeout is not applied to the DNS query). When
+          FEATURE_WGET_LONG_OPTIONS is also enabled, the --timeout option
+          will work in addition to -T.
 
 config ZCIP
         bool "zcip"
diff --git a/networking/wget.c b/networking/wget.c
index 5dac2b500..a32f85229 100644
--- a/networking/wget.c
+++ b/networking/wget.c
@@ -72,6 +72,7 @@ struct globals {
         const char *user_agent; /* "User-Agent" header field */
 #if ENABLE_FEATURE_WGET_TIMEOUT
         unsigned timeout_seconds;
+        bool connecting;
 #endif
         int output_fd;
         int o_flags;
@@ -87,7 +88,6 @@ struct globals {
 #define G (*ptr_to_globals)
 #define INIT_G() do { \
         SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
-        IF_FEATURE_WGET_TIMEOUT(G.timeout_seconds = 900;) \
 } while (0)
 
 
@@ -195,13 +195,27 @@ static char* sanitize_string(char *s)
         return s;
 }
 
+#if ENABLE_FEATURE_WGET_TIMEOUT
+static void alarm_handler(int sig UNUSED_PARAM)
+{
+        /* This is theoretically unsafe (uses stdio and malloc in signal handler) */
+        if (G.connecting)
+                bb_error_msg_and_die("download timed out");
+}
+#endif
+
 static FILE *open_socket(len_and_sockaddr *lsa)
 {
+        int fd;
         FILE *fp;
 
+        IF_FEATURE_WGET_TIMEOUT(alarm(G.timeout_seconds); G.connecting = 1;)
+        fd = xconnect_stream(lsa);
+        IF_FEATURE_WGET_TIMEOUT(G.connecting = 0;)
+
         /* glibc 2.4 seems to try seeking on it - ??! */
         /* hopefully it understands what ESPIPE means... */
-        fp = fdopen(xconnect_stream(lsa), "r+");
+        fp = fdopen(fd, "r+");
         if (fp == NULL)
                 bb_perror_msg_and_die(bb_msg_memory_exhausted);
 
@@ -209,6 +223,7 @@ static FILE *open_socket(len_and_sockaddr *lsa)
 }
 
 /* Returns '\n' if it was seen, else '\0'. Trims at first '\r' or '\n' */
+/* FIXME: does not respect FEATURE_WGET_TIMEOUT and -T N: */
 static char fgets_and_trim(FILE *fp)
 {
         char c;
@@ -944,7 +959,10 @@ int wget_main(int argc UNUSED_PARAM, char **argv)
 
         INIT_G();
 
-        IF_FEATURE_WGET_TIMEOUT(G.timeout_seconds = 900;)
+#if ENABLE_FEATURE_WGET_TIMEOUT
+        G.timeout_seconds = 900;
+        signal(SIGALRM, alarm_handler);
+#endif
         G.proxy_flag = "on";   /* use proxies if env vars are set */
         G.user_agent = "Wget"; /* "User-Agent" header field */