Merge branch 'revert-1691' into 'master'

Revert !1691 ("os: log: consolidate sigsafe and non-sigsafe logging paths")

See merge request xorg/xserver!2036

dix/dixfonts.c

@@ -2026,18 +2026,12 @@ static uint32_t wrap_time_in_millis(void)
     return GetTimeInMillis();
 }
 
-static void verrorf(const char *f, va_list args) _X_ATTRIBUTE_PRINTF(1, 0);
-static void verrorf(const char *f, va_list args)
-{
-    LogVMessageVerb(X_NONE, -1, f, args);
-}
-
 static const xfont2_client_funcs_rec xfont2_client_funcs = {
     .version = XFONT2_CLIENT_FUNCS_VERSION,
     .client_auth_generation = _client_auth_generation,
     .client_signal = ClientSignal,
     .delete_font_client_id = delete_font_client_id,
-    .verrorf = verrorf,
+    .verrorf = VErrorF,
     .find_old_font = find_old_font,
     .get_client_resolutions = get_client_resolutions,
     .get_default_point_size = get_default_point_size,

dix/getevents.c

@@ -1964,7 +1964,7 @@ GetTouchEvents(InternalEvent *events, DeviceIntPtr dev, uint32_t ddx_touchid,
 
     ti = TouchFindByDDXID(dev, ddx_touchid, (type == XI_TouchBegin));
     if (!ti) {
-        ErrorF("[dix] %s: unable to %s touch point %u\n", dev->name,
+        ErrorFSigSafe("[dix] %s: unable to %s touch point %u\n", dev->name,
                       type == XI_TouchBegin ? "begin" : "find", ddx_touchid);
         return 0;
     }
@@ -1998,14 +1998,16 @@ GetTouchEvents(InternalEvent *events, DeviceIntPtr dev, uint32_t ddx_touchid,
         if (!mask_in ||
             !valuator_mask_isset(mask_in, 0) ||
             !valuator_mask_isset(mask_in, 1)) {
-            ErrorF("%s: Attempted to start touch without x/y (driver bug)\n", dev->name);
+            ErrorFSigSafe("%s: Attempted to start touch without x/y "
+                          "(driver bug)\n", dev->name);
             return 0;
         }
         break;
     case XI_TouchUpdate:
         event->type = ET_TouchUpdate;
         if (!mask_in || valuator_mask_num_valuators(mask_in) <= 0) {
-            ErrorF("%s: TouchUpdate with no valuators? Driver bug\n", dev->name);
+            ErrorFSigSafe("%s: TouchUpdate with no valuators? Driver bug\n",
+                          dev->name);
         }
         break;
     case XI_TouchEnd:

dix/ptrveloc.c

@@ -78,7 +78,7 @@ DeletePredictableAccelerationProperties(DeviceIntPtr,
 /*#define PTRACCEL_DEBUGGING*/
 
 #ifdef PTRACCEL_DEBUGGING
-#define DebugAccelF(...) ErrorF("dix/ptraccel: " __VA_ARGS__)
+#define DebugAccelF(...) ErrorFSigSafe("dix/ptraccel: " __VA_ARGS__)
 #else
 #define DebugAccelF(...)        /* */
 #endif

glx/glxdri2.c

@@ -805,7 +805,7 @@ glxDRILeaveVT(ScrnInfoPtr scrn)
     __GLXDRIscreen *screen = (__GLXDRIscreen *)
         glxGetScreen(xf86ScrnToScreen(scrn));
 
-    LogMessageVerb(X_INFO, -1, "AIGLX: Suspending AIGLX clients for VT switch\n");
+    LogMessageVerbSigSafe(X_INFO, -1, "AIGLX: Suspending AIGLX clients for VT switch\n");
 
     glxSuspendClients();
 

hw/xfree86/common/xf86Init.c

@@ -856,12 +856,12 @@ ddxGiveUp(enum ExitCode error)
 void
 OsVendorFatalError(const char *f, va_list args)
 {
-    ErrorF("\nPlease consult the " XVENDORNAME " support \n\t at "
+    ErrorFSigSafe("\nPlease consult the " XVENDORNAME " support \n\t at "
                  __VENDORDWEBSUPPORT__ "\n for help. \n");
     if (xf86LogFile && xf86LogFileWasOpened)
-        ErrorF("Please also check the log file at \"%s\" for additional "
+        ErrorFSigSafe("Please also check the log file at \"%s\" for additional "
                      "information.\n", xf86LogFile);
-    ErrorF("\n");
+    ErrorFSigSafe("\n");
 }
 
 void

hw/xfree86/drivers/inputtest/xf86-input-inputtest.c

@@ -126,7 +126,7 @@ notify_sync_finished(ClientPtr ptr, void *closure)
         already shut down and the descriptor is closed.
     */
     if (write(fd, &response, response.header.length) != response.header.length) {
-        LogMessageVerb(X_ERROR, 0,
+        LogMessageVerbSigSafe(X_ERROR, 0,
                               "inputtest: Failed to write sync response: %s\n",
                               strerror(errno));
     }

hw/xfree86/int10/xf86x86emu.c

@@ -85,6 +85,6 @@ printk(const char *fmt, ...)
     va_list argptr;
 
     va_start(argptr, fmt);
-    LogVMessageVerb(X_NONE, -1, fmt, argptr);
+    VErrorF(fmt, argptr);
     va_end(argptr);
 }

hw/xfree86/loader/loader.c

@@ -141,7 +141,7 @@ LoaderSymbolFromModule(void *handle, const char *name)
 void
 LoaderUnload(const char *name, void *handle)
 {
-    LogMessageVerb(X_INFO, 1, "Unloading %s\n", name);
+    LogMessageVerbSigSafe(X_INFO, 1, "Unloading %s\n", name);
     if (handle)
         dlclose(handle);
 }

hw/xfree86/loader/loadmod.c

@@ -854,9 +854,9 @@ UnloadModule(void *_mod)
         const char *name = mod->VersionInfo->modname;
 
         if (mod->parent)
-            LogMessageVerb(X_INFO, 3, "UnloadSubModule: \"%s\"\n", name);
+            LogMessageVerbSigSafe(X_INFO, 3, "UnloadSubModule: \"%s\"\n", name);
         else
-            LogMessageVerb(X_INFO, 3, "UnloadModule: \"%s\"\n", name);
+            LogMessageVerbSigSafe(X_INFO, 3, "UnloadModule: \"%s\"\n", name);
 
         if (mod->TearDownData != ModuleDuplicated) {
             if ((mod->TearDownProc) && (mod->TearDownData))

hw/xfree86/parser/configProcs.h

@@ -145,4 +145,6 @@ xf86freeExtensions(XF86ConfExtensionsPtr ptr);
 /* Externally provided functions */
 void
 ErrorF(const char *f, ...);
+void
+VErrorF(const char *f, va_list args);
 #endif

hw/xfree86/parser/scan.c

@@ -974,7 +974,7 @@ xf86parseError(const char *format, ...)
     ErrorF("Parse error on line %d of section %s in file %s\n\t",
            configLineNo, configSection, filename);
     va_start(ap, format);
-    LogVMessageVerb(X_NONE, -1, format, ap);
+    VErrorF(format, ap);
     va_end(ap);
 
     ErrorF("\n");
@@ -989,7 +989,7 @@ xf86validationError(const char *format, ...)
 
     ErrorF("Data incomplete in file %s\n\t", filename);
     va_start(ap, format);
-    LogVMessageVerb(X_NONE, -1, format, ap);
+    VErrorF(format, ap);
     va_end(ap);
 
     ErrorF("\n");

hw/xwayland/xwayland-screen.c

@@ -90,7 +90,7 @@ xwl_give_up(const char *f, ...)
     va_list args;
 
     va_start(args, f);
-    LogVMessageVerb(X_NONE, -1, f, args);
+    VErrorFSigSafe(f, args);
     va_end(args);
 
     CloseWellKnownConnections();

hw/xwin/InitOutput.c

@@ -633,6 +633,9 @@ OsVendorInit(void)
 
     winFixupPaths();
 
+    if (!OsVendorVErrorFProc)
+        OsVendorVErrorFProc = OsVendorVErrorF;
+
     if (!g_fLogInited) {
         /* keep this order. If LogInit fails it calls Abort which then calls
          * ddxGiveUp where LogInit is called again and creates an infinite

hw/xwin/win.h

@@ -742,6 +742,10 @@ void
  * winerror.c
  */
 
+void
+OsVendorVErrorF(const char *pszFormat, va_list va_args)
+_X_ATTRIBUTE_PRINTF(1, 0);
+
 void
 winMessageBoxF(const char *pszError, UINT uType, ...)
 _X_ATTRIBUTE_PRINTF(1, 3);

hw/xwin/winerror.c

@@ -39,6 +39,23 @@
 
 #include "dix/input_priv.h"
 
+void
+OsVendorVErrorF(const char *pszFormat, va_list va_args)
+{
+    /* make sure the clipboard and multiwindow threads do not interfere the
+     * main thread */
+    static pthread_mutex_t s_pmPrinting = PTHREAD_MUTEX_INITIALIZER;
+
+    /* Lock the printing mutex */
+    pthread_mutex_lock(&s_pmPrinting);
+
+    /* Print the error message to a log file, could be stderr */
+    LogVMessageVerb(X_NONE, 0, pszFormat, va_args);
+
+    /* Unlock the printing mutex */
+    pthread_mutex_unlock(&s_pmPrinting);
+}
+
 /*
  * os/log.c:FatalError () calls our vendor ErrorF, so the message
  * from a FatalError will be logged.

hw/xwin/winprocarg.c

@@ -225,6 +225,12 @@ ddxProcessArgument(int argc, char *argv[], int i)
 
     /* Initialize once */
     if (!s_fBeenHere) {
+        /*
+         * This initialises our hook into VErrorF () for catching log messages
+         * that are generated before OsInit () is called.
+         */
+        OsVendorVErrorFProc = OsVendorVErrorF;
+
         s_fBeenHere = TRUE;
 
         /* Initialize only if option is not -help */

include/misc.h

@@ -377,10 +377,10 @@ extern _X_EXPORT unsigned long serverGeneration;
 /* Don't use this directly, use BUG_WARN or BUG_WARN_MSG instead */
 #define __BUG_WARN_MSG(cond, with_msg, ...)                                \
           do { if (cond) {                                                \
-              ErrorF("BUG: triggered 'if (" #cond ")'\n");          \
+              ErrorFSigSafe("BUG: triggered 'if (" #cond ")'\n");          \
-              ErrorF("BUG: %s:%u in %s()\n",                        \
+              ErrorFSigSafe("BUG: %s:%u in %s()\n",                        \
                            __FILE__, __LINE__, __func__);                 \
-              if (with_msg) ErrorF(__VA_ARGS__);                    \
+              if (with_msg) ErrorFSigSafe(__VA_ARGS__);                    \
               xorg_backtrace();                                           \
           } } while(0)
 

include/os.h

@@ -324,6 +324,12 @@ _X_ATTRIBUTE_PRINTF(3, 4);
 extern _X_EXPORT void
 LogMessage(MessageType type, const char *format, ...)
 _X_ATTRIBUTE_PRINTF(2, 3);
+extern _X_EXPORT void
+LogMessageVerbSigSafe(MessageType type, int verb, const char *format, ...)
+_X_ATTRIBUTE_PRINTF(3, 4);
+extern _X_EXPORT void
+LogVMessageVerbSigSafe(MessageType type, int verb, const char *format, va_list args)
+_X_ATTRIBUTE_PRINTF(3, 0);
 
 extern _X_EXPORT void
 LogVHdrMessageVerb(MessageType type, int verb,
@@ -349,10 +355,19 @@ _X_ATTRIBUTE_PRINTF(1, 2)
 #define DebugF(...)             /* */
 #endif
 
+extern _X_EXPORT void
+VErrorF(const char *f, va_list args)
+_X_ATTRIBUTE_PRINTF(1, 0);
 extern _X_EXPORT void
 ErrorF(const char *f, ...)
 _X_ATTRIBUTE_PRINTF(1, 2);
 extern _X_EXPORT void
+VErrorFSigSafe(const char *f, va_list args)
+_X_ATTRIBUTE_PRINTF(1, 0);
+extern _X_EXPORT void
+ErrorFSigSafe(const char *f, ...)
+_X_ATTRIBUTE_PRINTF(1, 2);
+extern _X_EXPORT void
 LogPrintMarkers(void);
 
 extern _X_EXPORT void
@@ -364,13 +379,6 @@ xorg_backtrace(void);
 typedef _sigset_t sigset_t;
 #endif
 
-/* should not be used anymore, just for backwards compat with drivers */
-#define LogVMessageVerbSigSafe(...) LogVMessageVerb(__VA_ARGS__)
-#define LogMessageVerbSigSafe(...) LogMessageVerb(__VA_ARGS__)
-#define ErrorFSigSafe(...) ErrorF(__VA_ARGS__)
-#define VErrorFSigSafe(...) VErrorF(__VA_ARGS__)
-#define VErrorF(...) LogVMessageVerb(X_NONE, -1, __VA_ARGS__)
-
 /* only for backwards compat with drivers that haven't kept up yet
    (xf86-video-intel)
 

mi/mieq.c

@@ -227,21 +227,21 @@ mieqEnqueue(DeviceIntPtr pDev, InternalEvent *e)
              */
             miEventQueue.dropped++;
             if (miEventQueue.dropped == 1) {
-                ErrorF("[mi] EQ overflowing.  Additional events will be "
+                ErrorFSigSafe("[mi] EQ overflowing.  Additional events will be "
                               "discarded until existing events are processed.\n");
                 xorg_backtrace();
-                ErrorF("[mi] These backtraces from mieqEnqueue may point to "
+                ErrorFSigSafe("[mi] These backtraces from mieqEnqueue may point to "
                               "a culprit higher up the stack.\n");
-                ErrorF("[mi] mieq is *NOT* the cause.  It is a victim.\n");
+                ErrorFSigSafe("[mi] mieq is *NOT* the cause.  It is a victim.\n");
             }
             else if (miEventQueue.dropped % QUEUE_DROP_BACKTRACE_FREQUENCY == 0 &&
                      miEventQueue.dropped / QUEUE_DROP_BACKTRACE_FREQUENCY <=
                      QUEUE_DROP_BACKTRACE_MAX) {
-                ErrorF("[mi] EQ overflow continuing.  %zu events have been "
+                ErrorFSigSafe("[mi] EQ overflow continuing.  %zu events have been "
                               "dropped.\n", miEventQueue.dropped);
                 if (miEventQueue.dropped / QUEUE_DROP_BACKTRACE_FREQUENCY ==
                     QUEUE_DROP_BACKTRACE_MAX) {
-                    ErrorF("[mi] No further overflow reports will be "
+                    ErrorFSigSafe("[mi] No further overflow reports will be "
                                   "reported until the clog is cleared.\n");
                 }
                 xorg_backtrace();

os/backtrace.c

@@ -82,21 +82,21 @@ print_registers(int frame, unw_cursor_t cursor)
     frame++;
     ret = unw_step(&cursor);
     if (ret < 0) {
-        ErrorF("unw_step failed: %s [%d]\n", unw_strerror(ret), ret);
+        ErrorFSigSafe("unw_step failed: %s [%d]\n", unw_strerror(ret), ret);
         return;
     }
 
-    ErrorF("\n");
+    ErrorFSigSafe("\n");
-    ErrorF("Registers at frame #%d:\n", frame);
+    ErrorFSigSafe("Registers at frame #%d:\n", frame);
 
     for (i = 0; i < num_regs; i++) {
         unw_word_t val;
         ret = unw_get_reg(&cursor, regs[i].regnum, &val);
         if (ret < 0) {
-            ErrorF("unw_get_reg(%s) failed: %s [%d]\n",
+            ErrorFSigSafe("unw_get_reg(%s) failed: %s [%d]\n",
                           regs[i].name, unw_strerror(ret), ret);
         } else {
-            ErrorF("  %s: 0x%" PRIxPTR "\n", regs[i].name, val);
+            ErrorFSigSafe("  %s: 0x%" PRIxPTR "\n", regs[i].name, val);
         }
     }
 }
@@ -117,23 +117,26 @@ xorg_backtrace(void)
     pip.unwind_info = NULL;
     ret = unw_getcontext(&context);
     if (ret) {
-        ErrorF("unw_getcontext failed: %s [%d]\n", unw_strerror(ret), ret);
+        ErrorFSigSafe("unw_getcontext failed: %s [%d]\n", unw_strerror(ret),
+                ret);
         return;
     }
 
     ret = unw_init_local(&cursor, &context);
     if (ret) {
-        ErrorF("unw_init_local failed: %s [%d]\n", unw_strerror(ret), ret);
+        ErrorFSigSafe("unw_init_local failed: %s [%d]\n", unw_strerror(ret),
+                ret);
         return;
     }
 
-    ErrorF("\n");
+    ErrorFSigSafe("\n");
-    ErrorF("Backtrace:\n");
+    ErrorFSigSafe("Backtrace:\n");
     ret = unw_step(&cursor);
     while (ret > 0) {
         ret = unw_get_proc_info(&cursor, &pip);
         if (ret) {
-            ErrorF("unw_get_proc_info failed: %s [%d]\n", unw_strerror(ret), ret);
+            ErrorFSigSafe("unw_get_proc_info failed: %s [%d]\n",
+                    unw_strerror(ret), ret);
             break;
         }
 
@@ -141,7 +144,8 @@ xorg_backtrace(void)
         ret = unw_get_proc_name(&cursor, procname, 256, &off);
         if (ret && ret != -UNW_ENOMEM) {
             if (ret != -UNW_EUNSPEC)
-                ErrorF("unw_get_proc_name failed: %s [%d]\n", unw_strerror(ret), ret);
+                ErrorFSigSafe("unw_get_proc_name failed: %s [%d]\n",
+                        unw_strerror(ret), ret);
             procname[0] = '?';
             procname[1] = 0;
         }
@@ -159,22 +163,22 @@ xorg_backtrace(void)
             signal_cursor = cursor;
             signal_frame = i;
 
-            ErrorF("%u: <signal handler called>\n", i++);
+            ErrorFSigSafe("%u: <signal handler called>\n", i++);
         } else {
-            ErrorF("%u: %s (%s%s+0x%x) [%p]\n", i++, filename, procname,
+            ErrorFSigSafe("%u: %s (%s%s+0x%x) [%p]\n", i++, filename, procname,
                 ret == -UNW_ENOMEM ? "..." : "", (int)off,
                 (void *)(uintptr_t)(ip));
         }
 
         ret = unw_step(&cursor);
         if (ret < 0)
-            ErrorF("unw_step failed: %s [%d]\n", unw_strerror(ret), ret);
+            ErrorFSigSafe("unw_step failed: %s [%d]\n", unw_strerror(ret), ret);
     }
 
     if (signal_frame >= 0)
         print_registers(signal_frame, signal_cursor);
 
-    ErrorF("\n");
+    ErrorFSigSafe("\n");
 }
 #else /* HAVE_LIBUNWIND */
 #ifdef HAVE_BACKTRACE
@@ -193,19 +197,19 @@ xorg_backtrace(void)
     int size, i;
     Dl_info info;
 
-    ErrorF("\n");
+    ErrorFSigSafe("\n");
-    ErrorF("Backtrace:\n");
+    ErrorFSigSafe("Backtrace:\n");
     size = backtrace(array, BT_SIZE);
     for (i = 0; i < size; i++) {
         int rc = dladdr(array[i], &info);
 
         if (rc == 0) {
-            ErrorF("%u: ?? [%p]\n", i, array[i]);
+            ErrorFSigSafe("%u: ?? [%p]\n", i, array[i]);
             continue;
         }
         mod = (info.dli_fname && *info.dli_fname) ? info.dli_fname : "(vdso)";
         if (info.dli_saddr)
-            ErrorF(
+            ErrorFSigSafe(
                 "%u: %s (%s+0x%x) [%p]\n",
                 i,
                 mod,
@@ -214,7 +218,7 @@ xorg_backtrace(void)
                                (char *) info.dli_saddr),
                 array[i]);
         else
-            ErrorF(
+            ErrorFSigSafe(
                 "%u: %s (%p+0x%x) [%p]\n",
                 i,
                 mod,
@@ -223,7 +227,7 @@ xorg_backtrace(void)
                                (char *) info.dli_fbase),
                 array[i]);
     }
-    ErrorF("\n");
+    ErrorFSigSafe("\n");
 }
 
 #else                           /* not glibc or glibc < 2.1 */
@@ -261,7 +265,7 @@ xorg_backtrace_frame(uintptr_t pc, int signo, void *arg)
             strcpy(signame, "unknown");
         }
 
-        ErrorF("** Signal %u (%s)\n", signo, signame);
+        ErrorFSigSafe("** Signal %u (%s)\n", signo, signame);
     }
 
     snprintf(header, sizeof(header), "%d: 0x%lx", depth, pc);
@@ -279,7 +283,8 @@ xorg_backtrace_frame(uintptr_t pc, int signo, void *arg)
             symname = "<section start>";
             offset = pc - (uintptr_t) dlinfo.dli_fbase;
         }
-        ErrorF("%s: %s:%s+0x%x\n", header, dlinfo.dli_fname, symname, offset);
+        ErrorFSigSafe("%s: %s:%s+0x%x\n", header, dlinfo.dli_fname, symname,
+                     offset);
 
     }
     else {
@@ -287,7 +292,7 @@ xorg_backtrace_frame(uintptr_t pc, int signo, void *arg)
          * probably poke elfloader here, but haven't written that code yet,
          * so we just print the pc.
          */
-        ErrorF("%s\n", header);
+        ErrorFSigSafe("%s\n", header);
     }
 
     return 0;
@@ -341,7 +346,7 @@ xorg_backtrace_pstack(void)
 
             if (bytesread > 0) {
                 btline[bytesread] = 0;
-                ErrorF("%s", btline);
+                ErrorFSigSafe("%s", btline);
             }
             else if ((bytesread < 0) || ((errno != EINTR) && (errno != EAGAIN)))
                 done = 1;
@@ -361,8 +366,8 @@ void
 xorg_backtrace(void)
 {
 
-    ErrorF("\n");
+    ErrorFSigSafe("\n");
-    ErrorF("Backtrace:\n");
+    ErrorFSigSafe("Backtrace:\n");
 
 #ifdef HAVE_PSTACK
 /* First try fork/exec of pstack - otherwise fall back to walkcontext
@@ -379,9 +384,9 @@ xorg_backtrace(void)
             walkcontext(&u, xorg_backtrace_frame, &depth);
         else
 #endif
-            ErrorF("Failed to get backtrace info: %s\n", strerror(errno));
+            ErrorFSigSafe("Failed to get backtrace info: %s\n", strerror(errno));
     }
-    ErrorF("\n");
+    ErrorFSigSafe("\n");
 }
 
 #else

os/log.c

@@ -105,6 +105,8 @@ OR PERFORMANCE OF THIS SOFTWARE.
 #pragma clang diagnostic ignored "-Wformat-nonliteral"
 #endif
 
+void (*OsVendorVErrorFProc) (const char *, va_list args) = NULL;
+
 /* Default logging parameters. */
 #define DEFAULT_LOG_VERBOSITY		0
 #define DEFAULT_LOG_FILE_VERBOSITY	3
@@ -300,7 +302,7 @@ LogClose(enum ExitCode error)
 {
     if (logFile) {
         int msgtype = (error == EXIT_NO_ERROR) ? X_INFO : X_ERROR;
-        LogMessageVerb(msgtype, -1,
+        LogMessageVerbSigSafe(msgtype, -1,
                 "Server terminated %s (%d). Closing log file.\n",
                 (error == EXIT_NO_ERROR) ? "successfully" : "with error",
                 error);
@@ -549,6 +551,19 @@ vpnprintf(char *string, int size_in, const char *f, va_list args)
     return s_idx;
 }
 
+static int
+pnprintf(char *string, int size, const char *f, ...)
+{
+    int rc;
+    va_list args;
+
+    va_start(args, f);
+    rc = vpnprintf(string, size, f, args);
+    va_end(args);
+
+    return rc;
+}
+
 /* This function does the actual log message writes. It must be signal safe.
  * When attempting to call non-signal-safe functions, guard them with a check
  * of the inSignalContext global variable. */
@@ -651,49 +666,40 @@ LogMessageTypeVerbString(MessageType type, int verb)
     }
 }
 
-#define LOG_MSG_BUF_SIZE 1024
-
-static ssize_t prepMsgHdr(MessageType type, int verb, char *buf)
-{
-    const char *type_str = LogMessageTypeVerbString(type, verb);
-    if (!type_str)
-        return -1;
-
-    size_t prefixLen = strlen_sigsafe(type_str);
-    if (prefixLen) {
-        memcpy(buf, type_str, prefixLen + 1); // rely on buffer being big enough
-        buf[prefixLen] = ' ';
-        prefixLen++;
-    }
-    buf[prefixLen] = 0;
-    return prefixLen;
-}
-
-static inline void writeLog(int verb, char *buf, int len)
-{
-    /* Force '\n' at end of truncated line */
-    if (LOG_MSG_BUF_SIZE  - len == 1)
-        buf[len - 1] = '\n';
-
-    LogSWrite(verb, buf, len, (buf[len - 1] == '\n'));
-}
-
-/* signal safe */
 void
 LogVMessageVerb(MessageType type, int verb, const char *format, va_list args)
 {
-    char buf[LOG_MSG_BUF_SIZE];
+    const char *type_str;
+    char buf[1024];
+    const size_t size = sizeof(buf);
+    Bool newline;
+    size_t len = 0;
 
-    size_t len = prepMsgHdr(type, verb, buf);
+    if (inSignalContext) {
-    if (len == -1)
+        LogVMessageVerbSigSafe(type, verb, format, args);
+        return;
+    }
+
+    type_str = LogMessageTypeVerbString(type, verb);
+    if (!type_str)
         return;
 
-    len += vpnprintf(&buf[len], sizeof(buf) - len, format, args);
+    /* if type_str is not "", prepend it and ' ', to message */
+    if (type_str[0] != '\0')
+        len += Xscnprintf(&buf[len], size - len, "%s ", type_str);
 
-    writeLog(verb, buf, len);
+    if (size - len > 1)
+        len += Xvscnprintf(&buf[len], size - len, format, args);
+
+    /* Force '\n' at end of truncated line */
+    if (size - len == 1)
+        buf[len - 1] = '\n';
+
+    newline = (buf[len - 1] == '\n');
+    LogSWrite(verb, buf, len, newline);
 }
 
-/* Log message with verbosity level specified. -- signal safe */
+/* Log message with verbosity level specified. */
 void
 LogMessageVerb(MessageType type, int verb, const char *format, ...)
 {
@@ -715,23 +721,86 @@ LogMessage(MessageType type, const char *format, ...)
     va_end(ap);
 }
 
+/* Log a message using only signal safe functions. */
+void
+LogMessageVerbSigSafe(MessageType type, int verb, const char *format, ...)
+{
+    va_list ap;
+    va_start(ap, format);
+    LogVMessageVerbSigSafe(type, verb, format, ap);
+    va_end(ap);
+}
+
+void
+LogVMessageVerbSigSafe(MessageType type, int verb, const char *format, va_list args)
+{
+    const char *type_str;
+    char buf[1024];
+    int len;
+    Bool newline;
+
+    type_str = LogMessageTypeVerbString(type, verb);
+    if (!type_str)
+        return;
+
+    /* if type_str is not "", prepend it and ' ', to message */
+    if (type_str[0] != '\0') {
+        LogSWrite(verb, type_str, strlen_sigsafe(type_str), FALSE);
+        LogSWrite(verb, " ", 1, FALSE);
+    }
+
+    len = vpnprintf(buf, sizeof(buf), format, args);
+
+    /* Force '\n' at end of truncated line */
+    if (sizeof(buf) - len == 1)
+        buf[len - 1] = '\n';
+
+    newline = (len > 0 && buf[len - 1] == '\n');
+    LogSWrite(verb, buf, len, newline);
+}
+
 void
 LogVHdrMessageVerb(MessageType type, int verb, const char *msg_format,
                    va_list msg_args, const char *hdr_format, va_list hdr_args)
 {
-    char buf[LOG_MSG_BUF_SIZE];
+    const char *type_str;
+    char buf[1024];
+    const size_t size = sizeof(buf);
+    Bool newline;
+    size_t len = 0;
+    int (*vprintf_func)(char *, int, const char* _X_RESTRICT_KYWD f, va_list args)
+            _X_ATTRIBUTE_PRINTF(3, 0);
+    int (*printf_func)(char *, int, const char* _X_RESTRICT_KYWD f, ...)
+            _X_ATTRIBUTE_PRINTF(3, 4);
 
-    size_t len = prepMsgHdr(type, verb, buf);
+    type_str = LogMessageTypeVerbString(type, verb);
-    if (len == -1)
+    if (!type_str)
         return;
 
-    if (hdr_format && sizeof(buf) - len > 1)
+    if (inSignalContext) {
-        len += vpnprintf(&buf[len], sizeof(buf) - len, hdr_format, hdr_args);
+        vprintf_func = vpnprintf;
+        printf_func = pnprintf;
+    } else {
+        vprintf_func = Xvscnprintf;
+        printf_func = Xscnprintf;
+    }
 
-    if (msg_format && sizeof(buf) - len > 1)
+    /* if type_str is not "", prepend it and ' ', to message */
-        len += vpnprintf(&buf[len], sizeof(buf) - len, msg_format, msg_args);
+    if (type_str[0] != '\0')
+        len += printf_func(&buf[len], size - len, "%s ", type_str);
 
-    writeLog(verb, buf, len);
+    if (hdr_format && size - len > 1)
+        len += vprintf_func(&buf[len], size - len, hdr_format, hdr_args);
+
+    if (msg_format && size - len > 1)
+        len += vprintf_func(&buf[len], size - len, msg_format, msg_args);
+
+    /* Force '\n' at end of truncated line */
+    if (size - len == 1)
+        buf[len - 1] = '\n';
+
+    newline = (buf[len - 1] == '\n');
+    LogSWrite(verb, buf, len, newline);
 }
 
 void
@@ -854,9 +923,9 @@ FatalError(const char *f, ...)
     static Bool beenhere = FALSE;
 
     if (beenhere)
-        ErrorF("\nFatalError re-entered, aborting\n");
+        ErrorFSigSafe("\nFatalError re-entered, aborting\n");
     else
-        ErrorF("\nFatal server error:\n");
+        ErrorFSigSafe("\nFatal server error:\n");
 
     va_start(args, f);
 
@@ -873,9 +942,9 @@ FatalError(const char *f, ...)
         va_end(apple_args);
     }
 #endif
-    LogVMessageVerb(X_NONE, -1, f, args);
+    VErrorFSigSafe(f, args);
     va_end(args);
-    ErrorF("\n");
+    ErrorFSigSafe("\n");
     if (!beenhere)
         OsVendorFatalError(f, args2);
     va_end(args2);
@@ -887,13 +956,38 @@ FatalError(const char *f, ...)
         OsAbort();
  /*NOTREACHED*/}
 
+void
+VErrorF(const char *f, va_list args)
+{
+    if (OsVendorVErrorFProc)
+        OsVendorVErrorFProc(f, args);
+    else
+        LogVMessageVerb(X_NONE, -1, f, args);
+}
+
 void
 ErrorF(const char *f, ...)
 {
     va_list args;
 
     va_start(args, f);
-    LogVMessageVerb(X_NONE, -1, f, args);
+    VErrorF(f, args);
+    va_end(args);
+}
+
+void
+VErrorFSigSafe(const char *f, va_list args)
+{
+    LogVMessageVerbSigSafe(X_ERROR, -1, f, args);
+}
+
+void
+ErrorFSigSafe(const char *f, ...)
+{
+    va_list args;
+
+    va_start(args, f);
+    VErrorFSigSafe(f, args);
     va_end(args);
 }
 

os/osdep.h

@@ -174,6 +174,10 @@ int os_move_fd(int fd);
    depending on whether multithreading is used */
 int xthread_sigmask(int how, const sigset_t *set, sigset_t *oldest);
 
+/* callback for DDX specific error printing, if any (may be NULL) */
+extern void (*OsVendorVErrorFProc) (const char *, va_list args)
+    _X_ATTRIBUTE_PRINTF(1, 0);
+
 typedef void (*OsSigHandlerPtr) (int sig);
 
 /* install signal handler */

os/osinit.c

@@ -119,8 +119,10 @@ OsSigHandler(int signo)
     if (signo == SIGNAL_FOR_RTLD_ERROR) {
         const char *dlerr = dlerror();
 
-        if (dlerr)
+        if (dlerr) {
-            LogMessageVerb(X_ERROR, 1, "Dynamic loader error: %s\n", dlerr);
+            LogMessageVerbSigSafe(X_ERROR, 1,
+                                  "Dynamic loader error: %s\n", dlerr);
+        }
     }
 #endif                          /* RTLD_DI_SETSIGNAL */
 
@@ -136,7 +138,7 @@ OsSigHandler(int signo)
 
 #ifdef SA_SIGINFO
     if (sip->si_code == SI_USER) {
-        ErrorF("Received signal %u sent by process %u, uid %u\n", signo,
+        ErrorFSigSafe("Received signal %u sent by process %u, uid %u\n", signo,
                      sip->si_pid, sip->si_uid);
     }
     else {
@@ -145,7 +147,7 @@ OsSigHandler(int signo)
         case SIGBUS:
         case SIGILL:
         case SIGFPE:
-            ErrorF("%s at address %p\n", strsignal(signo), sip->si_addr);
+            ErrorFSigSafe("%s at address %p\n", strsignal(signo), sip->si_addr);
         }
     }
 #endif

test/signal-logging.c

@@ -202,59 +202,59 @@ static void logging_format(void)
     } while (0)
 
     /* boring test message */
-    LogMessageVerb(X_ERROR, 1, "test message\n");
+    LogMessageVerbSigSafe(X_ERROR, 1, "test message\n");
     read_log_msg(logmsg);
     assert(strcmp(logmsg, "(EE) test message\n") == 0);
 
     /* long buf is truncated to "....en\n" */
-    LogMessageVerb(X_ERROR, 1, buf);
+    LogMessageVerbSigSafe(X_ERROR, 1, buf);
     read_log_msg(logmsg);
     assert(strcmp(&logmsg[strlen(logmsg) - 3], "en\n") == 0);
 
     /* same thing, this time as string substitution */
-    LogMessageVerb(X_ERROR, 1, "%s", buf);
+    LogMessageVerbSigSafe(X_ERROR, 1, "%s", buf);
     read_log_msg(logmsg);
     assert(strcmp(&logmsg[strlen(logmsg) - 3], "en\n") == 0);
 
     /* strings containing placeholders should just work */
-    LogMessageVerb(X_ERROR, 1, "%s\n", str);
+    LogMessageVerbSigSafe(X_ERROR, 1, "%s\n", str);
     read_log_msg(logmsg);
     assert(strcmp(logmsg, "(EE) %s %d %u %% %p %i\n") == 0);
 
     /* literal % */
-    LogMessageVerb(X_ERROR, 1, "test %%\n");
+    LogMessageVerbSigSafe(X_ERROR, 1, "test %%\n");
     read_log_msg(logmsg);
     assert(strcmp(logmsg, "(EE) test %\n") == 0);
 
     /* character */
-    LogMessageVerb(X_ERROR, 1, "test %c\n", 'a');
+    LogMessageVerbSigSafe(X_ERROR, 1, "test %c\n", 'a');
     read_log_msg(logmsg);
     assert(strcmp(logmsg, "(EE) test a\n") == 0);
 
     /* something unsupported % */
-    LogMessageVerb(X_ERROR, 1, "test %Q\n");
+    LogMessageVerbSigSafe(X_ERROR, 1, "test %Q\n");
     read_log_msg(logmsg);
     assert(strstr(logmsg, "BUG") != NULL);
-    LogMessageVerb(X_ERROR, 1, "\n");
+    LogMessageVerbSigSafe(X_ERROR, 1, "\n");
     fseek(f, 0, SEEK_END);
 
     /* string substitution */
-    LogMessageVerb(X_ERROR, 1, "%s\n", "substituted string");
+    LogMessageVerbSigSafe(X_ERROR, 1, "%s\n", "substituted string");
     read_log_msg(logmsg);
     assert(strcmp(logmsg, "(EE) substituted string\n") == 0);
 
     /* Invalid format */
-    LogMessageVerb(X_ERROR, 1, "%4", 4);
+    LogMessageVerbSigSafe(X_ERROR, 1, "%4", 4);
     read_log_msg(logmsg);
     assert(strcmp(logmsg, "(EE) ") == 0);
-    LogMessageVerb(X_ERROR, 1, "\n");
+    LogMessageVerbSigSafe(X_ERROR, 1, "\n");
     fseek(f, 0, SEEK_END);
 
     /* %hld is bogus */
-    LogMessageVerb(X_ERROR, 1, "%hld\n", 4);
+    LogMessageVerbSigSafe(X_ERROR, 1, "%hld\n", 4);
     read_log_msg(logmsg);
     assert(strstr(logmsg, "BUG") != NULL);
-    LogMessageVerb(X_ERROR, 1, "\n");
+    LogMessageVerbSigSafe(X_ERROR, 1, "\n");
     fseek(f, 0, SEEK_END);
 
     /* number substitution */
@@ -262,12 +262,12 @@ static void logging_format(void)
     do {
         char expected[30];
         sprintf(expected, "(EE) %u\n", ui);
-        LogMessageVerb(X_ERROR, 1, "%u\n", ui);
+        LogMessageVerbSigSafe(X_ERROR, 1, "%u\n", ui);
         read_log_msg(logmsg);
         assert(strcmp(logmsg, expected) == 0);
 
         sprintf(expected, "(EE) %x\n", ui);
-        LogMessageVerb(X_ERROR, 1, "%x\n", ui);
+        LogMessageVerbSigSafe(X_ERROR, 1, "%x\n", ui);
         read_log_msg(logmsg);
         assert(strcmp(logmsg, expected) == 0);
 
@@ -281,21 +281,21 @@ static void logging_format(void)
     do {
         char expected[30];
         sprintf(expected, "(EE) %lu\n", lui);
-        LogMessageVerb(X_ERROR, 1, "%lu\n", lui);
+        LogMessageVerbSigSafe(X_ERROR, 1, "%lu\n", lui);
         read_log_msg(logmsg);
 
         sprintf(expected, "(EE) %lld\n", (unsigned long long)ui);
-        LogMessageVerb(X_ERROR, 1, "%lld\n", (unsigned long long)ui);
+        LogMessageVerbSigSafe(X_ERROR, 1, "%lld\n", (unsigned long long)ui);
         read_log_msg(logmsg);
         assert(strcmp(logmsg, expected) == 0);
 
         sprintf(expected, "(EE) %lx\n", lui);
-        LogMessageVerb(X_ERROR, 1, "%lx\n", lui);
+        LogMessageVerbSigSafe(X_ERROR, 1, "%lx\n", lui);
         read_log_msg(logmsg);
         assert(strcmp(logmsg, expected) == 0);
 
         sprintf(expected, "(EE) %llx\n", (unsigned long long)ui);
-        LogMessageVerb(X_ERROR, 1, "%llx\n", (unsigned long long)ui);
+        LogMessageVerbSigSafe(X_ERROR, 1, "%llx\n", (unsigned long long)ui);
         read_log_msg(logmsg);
         assert(strcmp(logmsg, expected) == 0);
 
@@ -310,12 +310,12 @@ static void logging_format(void)
     do {
         char expected[30];
         sprintf(expected, "(EE) %d\n", i);
-        LogMessageVerb(X_ERROR, 1, "%d\n", i);
+        LogMessageVerbSigSafe(X_ERROR, 1, "%d\n", i);
         read_log_msg(logmsg);
         assert(strcmp(logmsg, expected) == 0);
 
         sprintf(expected, "(EE) %d\n", i | INT_MIN);
-        LogMessageVerb(X_ERROR, 1, "%d\n", i | INT_MIN);
+        LogMessageVerbSigSafe(X_ERROR, 1, "%d\n", i | INT_MIN);
         read_log_msg(logmsg);
         assert(strcmp(logmsg, expected) == 0);
 
@@ -329,22 +329,22 @@ static void logging_format(void)
     do {
         char expected[30];
         sprintf(expected, "(EE) %ld\n", li);
-        LogMessageVerb(X_ERROR, 1, "%ld\n", li);
+        LogMessageVerbSigSafe(X_ERROR, 1, "%ld\n", li);
         read_log_msg(logmsg);
         assert(strcmp(logmsg, expected) == 0);
 
         sprintf(expected, "(EE) %ld\n", li | LONG_MIN);
-        LogMessageVerb(X_ERROR, 1, "%ld\n", li | LONG_MIN);
+        LogMessageVerbSigSafe(X_ERROR, 1, "%ld\n", li | LONG_MIN);
         read_log_msg(logmsg);
         assert(strcmp(logmsg, expected) == 0);
 
         sprintf(expected, "(EE) %lld\n", (long long)li);
-        LogMessageVerb(X_ERROR, 1, "%lld\n", (long long)li);
+        LogMessageVerbSigSafe(X_ERROR, 1, "%lld\n", (long long)li);
         read_log_msg(logmsg);
         assert(strcmp(logmsg, expected) == 0);
 
         sprintf(expected, "(EE) %lld\n", (long long)(li | LONG_MIN));
-        LogMessageVerb(X_ERROR, 1, "%lld\n", (long long)(li | LONG_MIN));
+        LogMessageVerbSigSafe(X_ERROR, 1, "%lld\n", (long long)(li | LONG_MIN));
         read_log_msg(logmsg);
         assert(strcmp(logmsg, expected) == 0);
 
@@ -357,7 +357,7 @@ static void logging_format(void)
 
     /* pointer substitution */
     /* we print a null-pointer differently to printf */
-    LogMessageVerb(X_ERROR, 1, "%p\n", NULL);
+    LogMessageVerbSigSafe(X_ERROR, 1, "%p\n", NULL);
     read_log_msg(logmsg);
     assert(strcmp(logmsg, "(EE) 0x0\n") == 0);
 
@@ -369,7 +369,7 @@ static void logging_format(void)
 #else
         sprintf(expected, "(EE) %p\n", (void*)ptr);
 #endif
-        LogMessageVerb(X_ERROR, 1, "%p\n", (void*)ptr);
+        LogMessageVerbSigSafe(X_ERROR, 1, "%p\n", (void*)ptr);
         read_log_msg(logmsg);
         assert(strcmp(logmsg, expected) == 0);
         ptr <<= 1;
@@ -380,20 +380,20 @@ static void logging_format(void)
         double d = float_tests[i];
         char expected[30];
         sprintf(expected, "(EE) %.2f\n", d);
-        LogMessageVerb(X_ERROR, 1, "%f\n", d);
+        LogMessageVerbSigSafe(X_ERROR, 1, "%f\n", d);
         read_log_msg(logmsg);
         assert(strcmp(logmsg, expected) == 0);
 
         /* test for length modifiers, we just ignore them atm */
-        LogMessageVerb(X_ERROR, 1, "%.3f\n", d);
+        LogMessageVerbSigSafe(X_ERROR, 1, "%.3f\n", d);
         read_log_msg(logmsg);
         assert(strcmp(logmsg, expected) == 0);
 
-        LogMessageVerb(X_ERROR, 1, "%3f\n", d);
+        LogMessageVerbSigSafe(X_ERROR, 1, "%3f\n", d);
         read_log_msg(logmsg);
         assert(strcmp(logmsg, expected) == 0);
 
-        LogMessageVerb(X_ERROR, 1, "%.0f\n", d);
+        LogMessageVerbSigSafe(X_ERROR, 1, "%.0f\n", d);
         read_log_msg(logmsg);
         assert(strcmp(logmsg, expected) == 0);
     }