X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Flibsystemd-bus%2Fbus-error.c;h=25eaf0eee4961563535afc95b55e1ced63145169;hp=35e261464067abfe8c18807fcfeaaa4b4f0cc5c5;hb=c1b9d935725103e95901f347b8981647ce4dd546;hpb=c9b6cb28c35e18649575b82466d7d6eb29aa5196

diff --git a/src/libsystemd-bus/bus-error.c b/src/libsystemd-bus/bus-error.c
index 35e261464..25eaf0eee 100644
--- a/src/libsystemd-bus/bus-error.c
+++ b/src/libsystemd-bus/bus-error.c
@@ -27,86 +27,254 @@
 #include <stdio.h>
 
 #include "util.h"
+#include "errno-list.h"
 
 #include "sd-bus.h"
 #include "bus-error.h"
 
+#define BUS_ERROR_OOM SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_NO_MEMORY, "Out of memory")
+#define BUS_ERROR_FAILED SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_FAILED, "Operation failed")
+
+static int bus_error_name_to_errno(const char *name) {
+        const char *p;
+        int r;
+
+        if (!name)
+                return EINVAL;
+
+        p = startswith(name, "System.Error.");
+        if (p) {
+                r = errno_from_name(p);
+                if (r <= 0)
+                        return EIO;
+
+                return r;
+        }
+
+        /* Better replace this with a gperf table */
+
+        if (streq(name, SD_BUS_ERROR_NO_MEMORY))
+                return ENOMEM;
+
+        if (streq(name, SD_BUS_ERROR_SERVICE_UNKNOWN))
+                return EHOSTUNREACH;
+
+        if (streq(name, SD_BUS_ERROR_NAME_HAS_NO_OWNER))
+                return ENXIO;
+
+        if (streq(name, SD_BUS_ERROR_NO_REPLY) ||
+            streq(name, SD_BUS_ERROR_TIMEOUT) ||
+            streq(name, "org.freedesktop.DBus.Error.TimedOut"))
+                return ETIMEDOUT;
+
+        if (streq(name, SD_BUS_ERROR_IO_ERROR))
+                return EIO;
+
+        if (streq(name, SD_BUS_ERROR_BAD_ADDRESS))
+                return EADDRNOTAVAIL;
+
+        if (streq(name, SD_BUS_ERROR_NOT_SUPPORTED))
+                return ENOTSUP;
+
+        if (streq(name, SD_BUS_ERROR_LIMITS_EXCEEDED))
+                return ENOBUFS;
+
+        if (streq(name, SD_BUS_ERROR_ACCESS_DENIED) ||
+            streq(name, SD_BUS_ERROR_AUTH_FAILED))
+                return EACCES;
+
+        if (streq(name, SD_BUS_ERROR_NO_SERVER))
+                return EHOSTDOWN;
+
+        if (streq(name, SD_BUS_ERROR_NO_NETWORK))
+                return ENONET;
+
+        if (streq(name, SD_BUS_ERROR_ADDRESS_IN_USE))
+                return EADDRINUSE;
+
+        if (streq(name, SD_BUS_ERROR_DISCONNECTED))
+                return ECONNRESET;
+
+        if (streq(name, SD_BUS_ERROR_INVALID_ARGS) ||
+            streq(name, SD_BUS_ERROR_INVALID_SIGNATURE) ||
+            streq(name, "org.freedesktop.DBus.Error.MatchRuleInvalid") ||
+            streq(name, "org.freedesktop.DBus.Error.InvalidFileContent"))
+                return EINVAL;
+
+        if (streq(name, SD_BUS_ERROR_FILE_NOT_FOUND) ||
+            streq(name, "org.freedesktop.DBus.Error.MatchRuleNotFound"))
+                return ENOENT;
+
+        if (streq(name, SD_BUS_ERROR_FILE_EXISTS))
+                return EEXIST;
+
+        if (streq(name, SD_BUS_ERROR_UNKNOWN_METHOD) ||
+            streq(name, SD_BUS_ERROR_UNKNOWN_OBJECT) ||
+            streq(name, SD_BUS_ERROR_UNKNOWN_INTERFACE) ||
+            streq(name, SD_BUS_ERROR_UNKNOWN_PROPERTY))
+                return EBADR;
+
+        if (streq(name, SD_BUS_ERROR_PROPERTY_READ_ONLY))
+                return EROFS;
+
+        if (streq(name, SD_BUS_ERROR_UNIX_PROCESS_ID_UNKNOWN) ||
+            streq(name, "org.freedesktop.DBus.Error.SELinuxSecurityContextUnknown"))
+                return ESRCH;
+
+        if (streq(name, SD_BUS_ERROR_INCONSISTENT_MESSAGE))
+                return EBADMSG;
+
+        if (streq(name, "org.freedesktop.DBus.Error.ObjectPathInUse"))
+                return EBUSY;
+
+        return EIO;
+}
+
+static sd_bus_error errno_to_bus_error_const(int error) {
+
+        if (error < 0)
+                error = -error;
+
+        switch (error) {
+
+        case ENOMEM:
+                return BUS_ERROR_OOM;
+
+        case EPERM:
+        case EACCES:
+                return SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_ACCESS_DENIED, "Access denied");
+
+        case EINVAL:
+                return SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INVALID_ARGS, "Invalid argument");
+
+        case ESRCH:
+                return SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_UNIX_PROCESS_ID_UNKNOWN, "No such process");
+
+        case ENOENT:
+                return SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_FILE_NOT_FOUND, "File not found");
+
+        case EEXIST:
+                return SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_FILE_EXISTS, "File exists");
+
+        case ETIMEDOUT:
+        case ETIME:
+                return SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_TIMEOUT, "Timed out");
+
+        case EIO:
+                return SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_IO_ERROR, "Input/output error");
+
+        case ENETRESET:
+        case ECONNABORTED:
+        case ECONNRESET:
+                return SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_DISCONNECTED, "Disconnected");
+
+        case ENOTSUP:
+                return SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_NOT_SUPPORTED, "Not supported");
+
+        case EADDRNOTAVAIL:
+                return SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_BAD_ADDRESS, "Address not available");
+
+        case ENOBUFS:
+                return SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_LIMITS_EXCEEDED, "Limits exceeded");
+
+        case EADDRINUSE:
+                return SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_ADDRESS_IN_USE, "Address in use");
+
+        case EBADMSG:
+                return SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INCONSISTENT_MESSAGE, "Inconsistent message");
+        }
+
+        return SD_BUS_ERROR_NULL;
+}
+
+static int errno_to_bus_error_name_new(int error, char **ret) {
+        const char *name;
+        char *n;
+
+        if (error < 0)
+                error = -error;
+
+        name = errno_to_name(error);
+        if (!name)
+                return 0;
+
+        n = strappend("System.Error.", name);
+        if (!n)
+                return -ENOMEM;
+
+        *ret = n;
+        return 1;
+}
+
 bool bus_error_is_dirty(sd_bus_error *e) {
         if (!e)
-                return 0;
+                return false;
 
-        return e->name || e->message || e->need_free;
+        return e->name || e->message || e->_need_free != 0;
 }
 
-void sd_bus_error_free(sd_bus_error *e) {
+_public_ void sd_bus_error_free(sd_bus_error *e) {
         if (!e)
                 return;
 
-        if (e->need_free) {
+        if (e->_need_free > 0) {
                 free((void*) e->name);
                 free((void*) e->message);
         }
 
         e->name = e->message = NULL;
-        e->need_free = false;
+        e->_need_free = 0;
 }
 
-int sd_bus_error_set(sd_bus_error *e, const char *name, const char *message) {
-        char *n, *m = NULL;
+_public_ int sd_bus_error_set(sd_bus_error *e, const char *name, const char *message) {
 
-        if (!e)
+        if (!name)
                 return 0;
+        if (!e)
+                goto finish;
 
         assert_return(!bus_error_is_dirty(e), -EINVAL);
-        assert_return(name, -EINVAL);
 
-        n = strdup(name);
-        if (!n)
+        e->name = strdup(name);
+        if (!e->name) {
+                *e = BUS_ERROR_OOM;
                 return -ENOMEM;
-
-        if (message) {
-                m = strdup(message);
-                if (!m)
-                        return -ENOMEM;
         }
 
-        e->name = n;
-        e->message = m;
-        e->need_free = true;
+        if (message)
+                e->message = strdup(message);
+
+        e->_need_free = 1;
 
-        return 0;
+finish:
+        return -bus_error_name_to_errno(name);
 }
 
 int bus_error_setfv(sd_bus_error *e, const char *name, const char *format, va_list ap) {
-        char *n, *m = NULL;
-        int r;
 
-        if (!e)
+        if (!name)
                 return 0;
+        if (!e)
+                goto finish;
 
         assert_return(!bus_error_is_dirty(e), -EINVAL);
-        assert_return(name, -EINVAL);
 
-        n = strdup(name);
-        if (!n)
+        e->name = strdup(name);
+        if (!e->name) {
+                *e = BUS_ERROR_OOM;
                 return -ENOMEM;
-
-        if (format) {
-                r = vasprintf(&m, format, ap);
-                if (r < 0) {
-                        free(n);
-                        return -ENOMEM;
-                }
         }
 
-        e->name = n;
-        e->message = m;
-        e->need_free = true;
+        if (format)
+                vasprintf((char**) &e->message, format, ap);
+
+        e->_need_free = 1;
 
-        return 0;
+finish:
+        return -bus_error_name_to_errno(name);
 }
 
-int sd_bus_error_setf(sd_bus_error *e, const char *name, const char *format, ...) {
+_public_ int sd_bus_error_setf(sd_bus_error *e, const char *name, const char *format, ...) {
 
         if (format) {
                 int r;
@@ -122,165 +290,87 @@ int sd_bus_error_setf(sd_bus_error *e, const char *name, const char *format, ...
         return sd_bus_error_set(e, name, NULL);
 }
 
-int sd_bus_error_copy(sd_bus_error *dest, const sd_bus_error *e) {
-        char *x, *y = NULL;
+_public_ int sd_bus_error_copy(sd_bus_error *dest, const sd_bus_error *e) {
 
-        if (!dest)
-                return 0;
         if (!sd_bus_error_is_set(e))
                 return 0;
+        if (!dest)
+                goto finish;
 
         assert_return(!bus_error_is_dirty(dest), -EINVAL);
 
-        x = strdup(e->name);
-        if (!x)
-                return -ENOMEM;
-
-        if (e->message) {
-                y = strdup(e->message);
-                if (!y) {
-                        free(x);
+        /*
+         * _need_free  < 0 indicates that the error is temporarily const, needs deep copying
+         * _need_free == 0 indicates that the error is perpetually const, needs no deep copying
+         * _need_free  > 0 indicates that the error is fully dynamic, needs deep copying
+         */
+
+        if (e->_need_free == 0)
+                *dest = *e;
+        else {
+                dest->name = strdup(e->name);
+                if (!dest->name) {
+                        *dest = BUS_ERROR_OOM;
                         return -ENOMEM;
                 }
+
+                if (e->message)
+                        dest->message = strdup(e->message);
+
+                dest->_need_free = 1;
         }
 
-        dest->name = x;
-        dest->message = y;
-        dest->need_free = true;
-        return 0;
+finish:
+        return -bus_error_name_to_errno(e->name);
 }
 
-int sd_bus_error_set_const(sd_bus_error *e, const char *name, const char *message) {
-        if (!e)
+_public_ int sd_bus_error_set_const(sd_bus_error *e, const char *name, const char *message) {
+        if (!name)
                 return 0;
+        if (!e)
+                goto finish;
 
         assert_return(!bus_error_is_dirty(e), -EINVAL);
-        assert_return(name, -EINVAL);
 
-        *e = SD_BUS_ERROR_MAKE(name, message);
-        return 0;
+        *e = SD_BUS_ERROR_MAKE_CONST(name, message);
+
+finish:
+        return -bus_error_name_to_errno(name);
 }
 
-int sd_bus_error_is_set(const sd_bus_error *e) {
+_public_ int sd_bus_error_is_set(const sd_bus_error *e) {
         if (!e)
                 return 0;
 
         return !!e->name;
 }
 
-int sd_bus_error_has_name(const sd_bus_error *e, const char *name) {
+_public_ int sd_bus_error_has_name(const sd_bus_error *e, const char *name) {
         if (!e)
                 return 0;
 
         return streq_ptr(e->name, name);
 }
 
-int sd_bus_error_get_errno(const sd_bus_error* e) {
-
-        /* Better replce this with a gperf table */
-
+_public_ int sd_bus_error_get_errno(const sd_bus_error* e) {
         if (!e)
-                return EIO;
-
-        if (!e->name)
-                return EIO;
-
-        if (streq(e->name, SD_BUS_ERROR_NO_MEMORY))
-                return ENOMEM;
-
-        if (streq(e->name, SD_BUS_ERROR_SERVICE_UNKNOWN))
-                return EHOSTUNREACH;
-
-        if (streq(e->name, SD_BUS_ERROR_NAME_HAS_NO_OWNER))
-                return ENXIO;
-
-        if (streq(e->name, SD_BUS_ERROR_NO_REPLY) ||
-            streq(e->name, SD_BUS_ERROR_TIMEOUT) ||
-            streq(e->name, "org.freedesktop.DBus.Error.TimedOut"))
-                return ETIMEDOUT;
-
-        if (streq(e->name, SD_BUS_ERROR_IO_ERROR))
-                return EIO;
-
-        if (streq(e->name, SD_BUS_ERROR_BAD_ADDRESS))
-                return EADDRNOTAVAIL;
-
-        if (streq(e->name, SD_BUS_ERROR_NOT_SUPPORTED))
-                return ENOTSUP;
-
-        if (streq(e->name, SD_BUS_ERROR_LIMITS_EXCEEDED))
-                return ENOBUFS;
-
-        if (streq(e->name, SD_BUS_ERROR_ACCESS_DENIED) ||
-            streq(e->name, SD_BUS_ERROR_AUTH_FAILED))
-                return EACCES;
-
-        if (streq(e->name, SD_BUS_ERROR_NO_SERVER))
-                return EHOSTDOWN;
-
-        if (streq(e->name, SD_BUS_ERROR_NO_NETWORK))
-                return ENONET;
-
-        if (streq(e->name, SD_BUS_ERROR_ADDRESS_IN_USE))
-                return EADDRINUSE;
-
-        if (streq(e->name, SD_BUS_ERROR_DISCONNECTED))
-                return ECONNRESET;
-
-        if (streq(e->name, SD_BUS_ERROR_INVALID_ARGS) ||
-            streq(e->name, SD_BUS_ERROR_INVALID_SIGNATURE) ||
-            streq(e->name, "org.freedesktop.DBus.Error.MatchRuleInvalid") ||
-            streq(e->name, "org.freedesktop.DBus.Error.InvalidFileContent"))
-                return EINVAL;
-
-        if (streq(e->name, SD_BUS_ERROR_FILE_NOT_FOUND) ||
-            streq(e->name, "org.freedesktop.DBus.Error.MatchRuleNotFound"))
-                return ENOENT;
-
-        if (streq(e->name, SD_BUS_ERROR_FILE_EXISTS))
-                return EEXIST;
-
-        if (streq(e->name, SD_BUS_ERROR_UNKNOWN_METHOD) ||
-            streq(e->name, SD_BUS_ERROR_UNKNOWN_OBJECT) ||
-            streq(e->name, SD_BUS_ERROR_UNKNOWN_INTERFACE) ||
-            streq(e->name, SD_BUS_ERROR_UNKNOWN_PROPERTY))
-                return EBADR;
-
-        if (streq(e->name, SD_BUS_ERROR_PROPERTY_READ_ONLY))
-                return EROFS;
-
-        if (streq(e->name, SD_BUS_ERROR_UNIX_PROCESS_ID_UNKNOWN) ||
-            streq(e->name, "org.freedesktop.DBus.Error.SELinuxSecurityContextUnknown"))
-                return ESRCH;
-
-        if (streq(e->name, SD_BUS_ERROR_INCONSISTENT_MESSAGE))
-                return EBADMSG;
-
-        if (streq(e->name, "org.freedesktop.DBus.Error.ObjectPathInUse"))
-                return EBUSY;
+                return 0;
 
-        return EIO;
+        return bus_error_name_to_errno(e->name);
 }
 
-static int bus_error_set_strerror_or_const(sd_bus_error *e, const char *name, int error, const char *fallback) {
+static void bus_error_strerror(sd_bus_error *e, int error) {
         size_t k = 64;
-        char *n = NULL, *m = NULL;
-
-        if (error < 0)
-                error = -error;
-
-        if (!e)
-                return -error;
+        char *m;
 
-        assert_return(!bus_error_is_dirty(e), -EINVAL);
-        assert_return(name, -EINVAL);
+        assert(e);
 
         for (;;) {
                 char *x;
 
                 m = new(char, k);
                 if (!m)
-                        goto use_fallback;
+                        return;
 
                 errno = 0;
                 x = strerror_r(error, m, k);
@@ -292,143 +382,160 @@ static int bus_error_set_strerror_or_const(sd_bus_error *e, const char *name, in
 
                 if (!x || errno) {
                         free(m);
-                        goto use_fallback;
+                        return;
                 }
 
-
-                if (x != m) {
+                if (x == m) {
+                        if (e->_need_free > 0) {
+                                /* Error is already dynamic, let's just update the message */
+                                free((char*) e->message);
+                                e->message = x;
+
+                        } else {
+                                char *t;
+                                /* Error was const so far, let's make it dynamic, if we can */
+
+                                t = strdup(e->name);
+                                if (!t) {
+                                        free(m);
+                                        return;
+                                }
+
+                                e->_need_free = 1;
+                                e->name = t;
+                                e->message = x;
+                        }
+                } else {
                         free(m);
-                        sd_bus_error_set_const(e, name, x);
-                        return -error;
-                }
-
-                break;
-        }
-
 
-        n = strdup(name);
-        if (!n) {
-                free(m);
-                goto use_fallback;
-        }
+                        if (e->_need_free > 0) {
+                                char *t;
 
-        e->name = n;
-        e->message = m;
-        e->need_free = true;
+                                /* Error is dynamic, let's hence make the message also dynamic */
+                                t = strdup(x);
+                                if (!t)
+                                        return;
 
-        return -error;
+                                free((char*) e->message);
+                                e->message = t;
+                        } else {
+                                /* Error is const, hence we can just override */
+                                e->message = x;
+                        }
+                }
 
-use_fallback:
-        sd_bus_error_set_const(e, name, fallback);
-        return -error;
+                return;
+        }
 }
 
-static sd_bus_error map_from_errno(int error) {
+_public_ int sd_bus_error_set_errno(sd_bus_error *e, int error) {
 
         if (error < 0)
                 error = -error;
 
-        switch (error) {
-
-        case ENOMEM:
-                return SD_BUS_ERROR_MAKE(SD_BUS_ERROR_NO_NETWORK, "Out of memory");
-
-        case EPERM:
-        case EACCES:
-                return SD_BUS_ERROR_MAKE(SD_BUS_ERROR_ACCESS_DENIED, "Access denied");
-
-        case EINVAL:
-                return SD_BUS_ERROR_MAKE(SD_BUS_ERROR_INVALID_ARGS, "Invalid argument");
-
-        case ESRCH:
-                return SD_BUS_ERROR_MAKE(SD_BUS_ERROR_UNIX_PROCESS_ID_UNKNOWN, "No such process");
-
-        case ENOENT:
-                return SD_BUS_ERROR_MAKE(SD_BUS_ERROR_FILE_NOT_FOUND, "File not found");
-
-        case EEXIST:
-                return SD_BUS_ERROR_MAKE(SD_BUS_ERROR_FILE_EXISTS, "File exists");
-
-        case ETIMEDOUT:
-        case ETIME:
-                return SD_BUS_ERROR_MAKE(SD_BUS_ERROR_TIMEOUT, "Timed out");
-
-        case EIO:
-                return SD_BUS_ERROR_MAKE(SD_BUS_ERROR_IO_ERROR, "Input/output error");
-
-        case ENETRESET:
-        case ECONNABORTED:
-        case ECONNRESET:
-                return SD_BUS_ERROR_MAKE(SD_BUS_ERROR_DISCONNECTED, "Disconnected");
+        if (!e)
+                return -error;
+        if (error == 0)
+                return -error;
 
-        case ENOTSUP:
-                return SD_BUS_ERROR_MAKE(SD_BUS_ERROR_NOT_SUPPORTED, "Not supported");
+        assert_return(!bus_error_is_dirty(e), -EINVAL);
 
-        case EADDRNOTAVAIL:
-                return SD_BUS_ERROR_MAKE(SD_BUS_ERROR_BAD_ADDRESS, "Address not available");
+        /* First, try a const translation */
+        *e = errno_to_bus_error_const(error);
 
-        case ENOBUFS:
-                return SD_BUS_ERROR_MAKE(SD_BUS_ERROR_LIMITS_EXCEEDED, "Limits exceeded");
+        if (!sd_bus_error_is_set(e)) {
+                int k;
 
-        case EADDRINUSE:
-                return SD_BUS_ERROR_MAKE(SD_BUS_ERROR_ADDRESS_IN_USE, "Address in use");
+                /* If that didn't work, try a dynamic one. */
 
-        case EBADMSG:
-                return SD_BUS_ERROR_MAKE(SD_BUS_ERROR_INCONSISTENT_MESSAGE, "Inconsistent message");
+                k = errno_to_bus_error_name_new(error, (char**) &e->name);
+                if (k > 0)
+                        e->_need_free = 1;
+                else if (k < 0) {
+                        *e = BUS_ERROR_OOM;
+                        return -error;
+                } else
+                        *e = BUS_ERROR_FAILED;
         }
 
-        return SD_BUS_ERROR_MAKE(SD_BUS_ERROR_FAILED, "Operation failed");
-}
-
-int sd_bus_error_set_errno(sd_bus_error *e, int error) {
-        sd_bus_error x;
-
-        x = map_from_errno(error);
-
-        return bus_error_set_strerror_or_const(e, x.name, error, x.message);
+        /* Now, fill in the message from strerror() if we can */
+        bus_error_strerror(e, error);
+        return -error;
 }
 
 int bus_error_set_errnofv(sd_bus_error *e, int error, const char *format, va_list ap) {
-        sd_bus_error x;
         int r;
 
         if (error < 0)
                 error = -error;
 
         if (!e)
+                return -error;
+        if (error == 0)
                 return 0;
 
         assert_return(!bus_error_is_dirty(e), -EINVAL);
 
-        x = map_from_errno(error);
+        /* First, try a const translation */
+        *e = errno_to_bus_error_const(error);
+
+        if (!sd_bus_error_is_set(e)) {
+                int k;
+
+                /* If that didn't work, try a dynamic one */
+
+                k = errno_to_bus_error_name_new(error, (char**) &e->name);
+                if (k > 0)
+                        e->_need_free = 1;
+                else if (k < 0) {
+                        *e = BUS_ERROR_OOM;
+                        return -ENOMEM;
+                } else
+                        *e = BUS_ERROR_FAILED;
+        }
 
         if (format) {
-                char *n, *m;
+                char *m;
 
-                r = vasprintf(&m, format, ap);
-                if (r < 0)
-                        goto fallback;
+                /* First, let's try to fill in the supplied message */
 
-                n = strdup(x.name);
-                if (!n) {
-                        free(m);
-                        goto fallback;
+                r = vasprintf(&m, format, ap);
+                if (r >= 0) {
+
+                        if (e->_need_free <= 0) {
+                                char *t;
+
+                                t = strdup(e->name);
+                                if (t) {
+                                        e->_need_free = 1;
+                                        e->name = t;
+                                        e->message = m;
+                                        return -error;
+                                }
+
+                                free(m);
+                        } else {
+                                free((char*) e->message);
+                                e->message = m;
+                                return -error;
+                        }
                 }
-
-                e->name = n;
-                e->message = m;
-                e->need_free = true;
-                return -error;
         }
 
-fallback:
-        return bus_error_set_strerror_or_const(e, x.name, error, x.message);
+        /* If that didn't work, use strerror() for the message */
+        bus_error_strerror(e, error);
+        return -error;
 }
 
-int sd_bus_error_set_errnof(sd_bus_error *e, int error, const char *format, ...) {
+_public_ int sd_bus_error_set_errnof(sd_bus_error *e, int error, const char *format, ...) {
         int r;
 
+        if (error < 0)
+                error = -error;
+
         if (!e)
+                return -error;
+        if (error == 0)
                 return 0;
 
         assert_return(!bus_error_is_dirty(e), -EINVAL);