Patches from Debian
[nbd.git] / nbd-server.c
index 85a1e06..4d01e37 100644 (file)
@@ -68,6 +68,7 @@
 #include <sys/mount.h>         /* For BLKGETSIZE */
 #endif
 #include <signal.h>            /* sigaction */
+#include <errno.h>
 #include <netinet/tcp.h>
 #include <netinet/in.h>                /* sockaddr_in, htons, in_addr */
 #include <netdb.h>             /* hostent, gethostby*, getservby* */
@@ -138,7 +139,7 @@ gchar* rungroup=NULL;
  **/
 #define OFFT_MAX ~((off_t)1<<(sizeof(off_t)*8-1))
 #define LINELEN 256      /**< Size of static buffer used to read the
-                           authorization file (yuck) */
+                              authorization file (yuck) */
 #define BUFSIZE (1024*1024) /**< Size of buffer that can hold requests */
 #define DIFFPAGESIZE 4096 /**< diff file uses those chunks */
 #define F_READONLY 1      /**< flag to tell us a file is readonly */
@@ -146,7 +147,9 @@ gchar* rungroup=NULL;
 #define F_COPYONWRITE 4          /**< flag to tell us a file is exported using
                            copyonwrite */
 #define F_AUTOREADONLY 8  /**< flag to tell us a file is set to autoreadonly */
-#define F_SPARSE 16
+#define F_SPARSE 16      /**< flag to tell us copyronwrite should use a sparse file */
+#define F_SDP 32         /**< flag to tell us the export should be done using the Socket Direct Protocol for RDMA */
+#define F_SYNC 64        /**< Whether to fsync() after a write */
 GHashTable *children;
 char pidfname[256]; /**< name of our PID file */
 char pidftemplate[256]; /**< template to be used for the filename of the PID file */
@@ -170,15 +173,18 @@ typedef struct {
        gchar* exportname;    /**< (unprocessed) filename of the file we're exporting */
        off_t expected_size; /**< size of the exported file as it was told to
                               us through configuration */
+       gchar* listenaddr;   /**< The IP address we're listening on */
        unsigned int port;   /**< port we're exporting this file at */
        char* authname;      /**< filename of the authorization file */
        int flags;           /**< flags associated with this exported file */
-       unsigned int timeout;/**< how long a connection may be idle
-                              (0=forever) */
        int socket;          /**< The socket of this server. */
        VIRT_STYLE virtstyle;/**< The style of virtualization, if any */
        uint8_t cidrlen;     /**< The length of the mask when we use
                                  CIDR-style virtualization */
+       gchar* prerun;       /**< command to be ran after connecting a client,
+                                 but before starting to serve */
+       gchar* postrun;      /**< command that will be ran after the client
+                                 disconnects */
 } SERVER;
 
 /**
@@ -297,10 +303,14 @@ inline void readit(int f, void *buf, size_t len) {
        ssize_t res;
        while (len > 0) {
                DEBUG("*");
-               if ((res = read(f, buf, len)) <= 0)
-                       err("Read failed: %m");
-               len -= res;
-               buf += res;
+               if ((res = read(f, buf, len)) <= 0) {
+                       if(errno != EAGAIN) {
+                               err("Read failed: %m");
+                       }
+               } else {
+                       len -= res;
+                       buf += res;
+               }
        }
 }
 
@@ -328,7 +338,7 @@ inline void writeit(int f, void *buf, size_t len) {
  */
 void usage() {
        printf("This is nbd-server version " VERSION "\n");
-       printf("Usage: port file_to_export [size][kKmM] [-l authorize_file] [-r] [-m] [-c] [-a timeout_sec] [-C configuration file] [-p PID file name] [-o section name]\n"
+       printf("Usage: [ip:]port file_to_export [size][kKmM] [-l authorize_file] [-r] [-m] [-c] [-C configuration file] [-p PID file name] [-o section name]\n"
               "\t-r|--read-only\t\tread only\n"
               "\t-m|--multi-file\t\tmultiple file\n"
               "\t-c|--copy-on-write\tcopy on write\n"
@@ -339,7 +349,8 @@ void usage() {
               "\t-o|--output-config\toutput a config file section for what you\n\t\t\t\tspecified on the command line, with the\n\t\t\t\tspecified section name\n\n"
               "\tif port is set to 0, stdin is used (for running from inetd)\n"
               "\tif file_to_export contains '%%s', it is substituted with the IP\n"
-              "\t\taddress of the machine trying to connect\n" );
+              "\t\taddress of the machine trying to connect\n" 
+              "\tif ip is set, it contains the local IP address on which we're listening.\n\tif not, the server will listen on all local IP addresses\n");
        printf("Using configuration file %s\n", CFILE);
 }
 
@@ -347,6 +358,7 @@ void usage() {
 void dump_section(SERVER* serve, gchar* section_header) {
        printf("[%s]\n", section_header);
        printf("\texportname = %s\n", serve->exportname);
+       printf("\tlistenaddr = %s\n", serve->listenaddr);
        printf("\tport = %d\n", serve->port);
        if(serve->flags & F_READONLY) {
                printf("\treadonly = true\n");
@@ -358,14 +370,11 @@ void dump_section(SERVER* serve, gchar* section_header) {
                printf("\tcopyonwrite = true\n");
        }
        if(serve->expected_size) {
-               printf("\tfilesize = %Ld\n", (long long int)serve->expected_size);
+               printf("\tfilesize = %lld\n", (long long int)serve->expected_size);
        }
        if(serve->authname) {
                printf("\tauthfile = %s\n", serve->authname);
        }
-       if(serve->timeout) {
-               printf("\ttimeout = %d\n", serve->timeout);
-       }
        exit(EXIT_SUCCESS);
 }
 
@@ -395,20 +404,30 @@ SERVER* cmdline(int argc, char *argv[]) {
        size_t last;
        char suffix;
        gboolean do_output=FALSE;
-       gchar* section_header;
+       gchar* section_header="";
+       gchar** addr_port;
 
        if(argc==1) {
                return NULL;
        }
        serve=g_new0(SERVER, 1);
        serve->authname = g_strdup(default_authname);
+       serve->virtstyle=VIRT_IPLIT;
        while((c=getopt_long(argc, argv, "-a:C:cl:mo:rp:", long_options, &i))>=0) {
                switch (c) {
                case 1:
                        /* non-option argument */
                        switch(nonspecial++) {
                        case 0:
-                               serve->port=strtol(optarg, NULL, 0);
+                               addr_port=g_strsplit(optarg, ":", 2);
+                               if(addr_port[1]) {
+                                       serve->port=strtol(addr_port[1], NULL, 0);
+                                       serve->listenaddr=g_strdup(addr_port[0]);
+                               } else {
+                                       serve->listenaddr=g_strdup("0.0.0.0");
+                                       serve->port=strtol(addr_port[0], NULL, 0);
+                               }
+                               g_strfreev(addr_port);
                                break;
                        case 1:
                                serve->exportname = g_strdup(optarg);
@@ -423,7 +442,7 @@ SERVER* cmdline(int argc, char *argv[]) {
                                if (suffix == 'k' || suffix == 'K' ||
                                    suffix == 'm' || suffix == 'M')
                                        optarg[last] = '\0';
-                               es = (off_t)atol(optarg);
+                               es = (off_t)atoll(optarg);
                                switch (suffix) {
                                        case 'm':
                                        case 'M':  es <<= 10;
@@ -459,9 +478,6 @@ SERVER* cmdline(int argc, char *argv[]) {
                        g_free(serve->authname);
                        serve->authname=g_strdup(optarg);
                        break;
-               case 'a': 
-                       serve->timeout=strtol(optarg, NULL, 0);
-                       break;
                default:
                        usage();
                        exit(EXIT_FAILURE);
@@ -492,7 +508,10 @@ typedef enum {
        CFILE_MISSING_GENERIC,  /**< The (required) group "generic" is missing */
        CFILE_KEY_MISSING,      /**< A (required) key is missing */
        CFILE_VALUE_INVALID,    /**< A value is syntactically invalid */
-       CFILE_PROGERR           /**< Programmer error */
+       CFILE_VALUE_UNSUPPORTED,/**< A value is not supported in this build */
+       CFILE_PROGERR,          /**< Programmer error */
+       CFILE_NO_EXPORTS        /**< A config file was specified that does not
+                                    define any exports */
 } CFILE_ERRORS;
 
 /**
@@ -527,22 +546,25 @@ GArray* parse_cfile(gchar* f, GError** e) {
                { "exportname", TRUE,   PARAM_STRING,   NULL, 0 },
                { "port",       TRUE,   PARAM_INT,      NULL, 0 },
                { "authfile",   FALSE,  PARAM_STRING,   NULL, 0 },
-               { "timeout",    FALSE,  PARAM_INT,      NULL, 0 },
                { "filesize",   FALSE,  PARAM_INT,      NULL, 0 },
                { "virtstyle",  FALSE,  PARAM_STRING,   NULL, 0 },
+               { "prerun",     FALSE,  PARAM_STRING,   NULL, 0 },
+               { "postrun",    FALSE,  PARAM_STRING,   NULL, 0 },
                { "readonly",   FALSE,  PARAM_BOOL,     NULL, F_READONLY },
                { "multifile",  FALSE,  PARAM_BOOL,     NULL, F_MULTIFILE },
                { "copyonwrite", FALSE, PARAM_BOOL,     NULL, F_COPYONWRITE },
-               { "autoreadonly", FALSE, PARAM_BOOL,    NULL, F_AUTOREADONLY },
                { "sparse_cow", FALSE,  PARAM_BOOL,     NULL, F_SPARSE },
+               { "sdp",        FALSE,  PARAM_BOOL,     NULL, F_SDP },
+               { "sync",       FALSE,  PARAM_BOOL,     NULL, F_SYNC },
+               { "listenaddr", FALSE,  PARAM_STRING,   NULL, 0 },
        };
-       const int lp_size=11;
+       const int lp_size=sizeof(lp)/sizeof(PARAM);
        PARAM gp[] = {
                { "user",       FALSE, PARAM_STRING,    &runuser,       0 },
                { "group",      FALSE, PARAM_STRING,    &rungroup,      0 },
        };
        PARAM* p=gp;
-       int p_size=2;
+       int p_size=sizeof(gp)/sizeof(PARAM);
        GKeyFile *cfile;
        GError *err = NULL;
        const char *err_msg=NULL;
@@ -550,6 +572,7 @@ GArray* parse_cfile(gchar* f, GError** e) {
        GArray *retval=NULL;
        gchar **groups;
        gboolean value;
+       gchar* startgroup;
        gint i;
        gint j;
 
@@ -558,11 +581,12 @@ GArray* parse_cfile(gchar* f, GError** e) {
        retval = g_array_new(FALSE, TRUE, sizeof(SERVER));
        if(!g_key_file_load_from_file(cfile, f, G_KEY_FILE_KEEP_COMMENTS |
                        G_KEY_FILE_KEEP_TRANSLATIONS, &err)) {
-               g_set_error(e, errdomain, CFILE_NOTFOUND, "Could not open config file.");
+               g_set_error(e, errdomain, CFILE_NOTFOUND, "Could not open config file.", f);
                g_key_file_free(cfile);
                return retval;
        }
-       if(strcmp(g_key_file_get_start_group(cfile), "generic")) {
+       startgroup = g_key_file_get_start_group(cfile);
+       if(!startgroup || strcmp(startgroup, "generic")) {
                g_set_error(e, errdomain, CFILE_MISSING_GENERIC, "Config file does not contain the [generic] group!");
                g_key_file_free(cfile);
                return NULL;
@@ -573,11 +597,15 @@ GArray* parse_cfile(gchar* f, GError** e) {
                lp[0].target=&(s.exportname);
                lp[1].target=&(s.port);
                lp[2].target=&(s.authname);
-               lp[3].target=&(s.timeout);
-               lp[4].target=&(s.expected_size);
-               lp[5].target=&(virtstyle);
-               lp[6].target=lp[7].target=lp[8].target=
-                               lp[9].target=lp[10].target=&(s.flags);
+               lp[3].target=&(s.expected_size);
+               lp[4].target=&(virtstyle);
+               lp[5].target=&(s.prerun);
+               lp[6].target=&(s.postrun);
+               lp[7].target=lp[8].target=lp[9].target=
+                               lp[10].target=lp[11].target=
+                               lp[12].target=&(s.flags);
+               lp[13].target=&(s.listenaddr);
+
                /* After the [generic] group, start parsing exports */
                if(i==1) {
                        p=lp;
@@ -662,9 +690,24 @@ GArray* parse_cfile(gchar* f, GError** e) {
                virtstyle=NULL;
                /* Don't append values for the [generic] group */
                if(i>0) {
+                       if(!s.listenaddr) {
+                               s.listenaddr = g_strdup("0.0.0.0");
+                       }
                        g_array_append_val(retval, s);
                }
+#ifndef WITH_SDP
+               if(s.flags & F_SDP) {
+                       g_set_error(e, errdomain, CFILE_VALUE_UNSUPPORTED, "This nbd-server was built without support for SDP, yet group %s uses it", groups[i]);
+                       g_array_free(retval, TRUE);
+                       g_key_file_free(cfile);
+                       return NULL;
+               }
+#endif
        }
+       if(i==1) {
+               g_set_error(e, errdomain, CFILE_NO_EXPORTS, "The config file does not specify any exports");
+       }
+       g_key_file_free(cfile);
        return retval;
 }
 
@@ -722,7 +765,7 @@ void sigterm_handler(int s) {
                unlink(pidfname);
        }
 
-       exit(0);
+       exit(EXIT_SUCCESS);
 }
 
 /**
@@ -734,19 +777,18 @@ void sigterm_handler(int s) {
  **/
 off_t size_autodetect(int fhandle) {
        off_t es;
-       unsigned long sectors;
+       u64 bytes;
        struct stat stat_buf;
        int error;
 
 #ifdef HAVE_SYS_MOUNT_H
 #ifdef HAVE_SYS_IOCTL_H
-#ifdef BLKGETSIZE
-       DEBUG("looking for export size with ioctl BLKGETSIZE\n");
-       if (!ioctl(fhandle, BLKGETSIZE, &sectors) && sectors) {
-               es = (off_t)sectors * (off_t)512;
-               return es;
+#ifdef BLKGETSIZE64
+       DEBUG("looking for export size with ioctl BLKGETSIZE64\n");
+       if (!ioctl(fhandle, BLKGETSIZE64, bytes) && bytes) {
+               return (off_t)bytes;
        }
-#endif /* BLKGETSIZE */
+#endif /* BLKGETSIZE64 */
 #endif /* HAVE_SYS_IOCTL_H */
 #endif /* HAVE_SYS_MOUNT_H */
 
@@ -848,16 +890,21 @@ ssize_t rawexpwrite(off_t a, char *buf, size_t len, CLIENT *client) {
        int fhandle;
        off_t foffset;
        size_t maxbytes;
+       ssize_t retval;
 
        if(get_filepos(client->export, a, &fhandle, &foffset, &maxbytes))
                return -1;
        if(maxbytes && len > maxbytes)
                len = maxbytes;
 
-       DEBUG4("(WRITE to fd %d offset %Lu len %u), ", fhandle, foffset, len);
+       DEBUG4("(WRITE to fd %d offset %llu len %u), ", fhandle, foffset, len);
 
        myseek(fhandle, foffset);
-       return write(fhandle, buf, len);
+       retval = write(fhandle, buf, len);
+       if(client->server->flags & F_SYNC) {
+               fsync(fhandle);
+       }
+       return retval;
 }
 
 /**
@@ -865,7 +912,7 @@ ssize_t rawexpwrite(off_t a, char *buf, size_t len, CLIENT *client) {
  * @return 0 on success, nonzero on failure
  **/
 int rawexpwrite_fully(off_t a, char *buf, size_t len, CLIENT *client) {
-       ssize_t ret;
+       ssize_t ret=0;
 
        while(len > 0 && (ret=rawexpwrite(a, buf, len, client)) > 0 ) {
                a += ret;
@@ -896,7 +943,7 @@ ssize_t rawexpread(off_t a, char *buf, size_t len, CLIENT *client) {
        if(maxbytes && len > maxbytes)
                len = maxbytes;
 
-       DEBUG4("(READ from fd %d offset %Lu len %u), ", fhandle, foffset, len);
+       DEBUG4("(READ from fd %d offset %llu len %u), ", fhandle, foffset, len);
 
        myseek(fhandle, foffset);
        return read(fhandle, buf, len);
@@ -907,7 +954,7 @@ ssize_t rawexpread(off_t a, char *buf, size_t len, CLIENT *client) {
  * @return 0 on success, nonzero on failure
  **/
 int rawexpread_fully(off_t a, char *buf, size_t len, CLIENT *client) {
-       ssize_t ret;
+       ssize_t ret=0;
 
        while(len > 0 && (ret=rawexpread(a, buf, len, client)) > 0 ) {
                a += ret;
@@ -933,7 +980,7 @@ int expread(off_t a, char *buf, size_t len, CLIENT *client) {
 
        if (!(client->server->flags & F_COPYONWRITE))
                return(rawexpread_fully(a, buf, len, client));
-       DEBUG3("Asked to read %d bytes at %Lu.\n", len, (unsigned long long)a);
+       DEBUG3("Asked to read %d bytes at %llu.\n", len, (unsigned long long)a);
 
        mapl=a/DIFFPAGESIZE; maph=(a+len-1)/DIFFPAGESIZE;
 
@@ -943,12 +990,12 @@ int expread(off_t a, char *buf, size_t len, CLIENT *client) {
                rdlen=(0<DIFFPAGESIZE-offset && len<(size_t)(DIFFPAGESIZE-offset)) ?
                        len : (size_t)DIFFPAGESIZE-offset;
                if (client->difmap[mapcnt]!=(u32)(-1)) { /* the block is already there */
-                       DEBUG3("Page %Lu is at %lu\n", (unsigned long long)mapcnt,
+                       DEBUG3("Page %llu is at %lu\n", (unsigned long long)mapcnt,
                               (unsigned long)(client->difmap[mapcnt]));
                        myseek(client->difffile, client->difmap[mapcnt]*DIFFPAGESIZE+offset);
                        if (read(client->difffile, buf, rdlen) != rdlen) return -1;
                } else { /* the block is not there */
-                       DEBUG2("Page %Lu is not here, we read the original one\n",
+                       DEBUG2("Page %llu is not here, we read the original one\n",
                               (unsigned long long)mapcnt);
                        if(rawexpread_fully(a, buf, rdlen, client)) return -1;
                }
@@ -977,7 +1024,7 @@ int expwrite(off_t a, char *buf, size_t len, CLIENT *client) {
 
        if (!(client->server->flags & F_COPYONWRITE))
                return(rawexpwrite_fully(a, buf, len, client)); 
-       DEBUG3("Asked to write %d bytes at %Lu.\n", len, (unsigned long long)a);
+       DEBUG3("Asked to write %d bytes at %llu.\n", len, (unsigned long long)a);
 
        mapl=a/DIFFPAGESIZE ; maph=(a+len-1)/DIFFPAGESIZE ;
 
@@ -988,7 +1035,7 @@ int expwrite(off_t a, char *buf, size_t len, CLIENT *client) {
                        len : (size_t)DIFFPAGESIZE-offset;
 
                if (client->difmap[mapcnt]!=(u32)(-1)) { /* the block is already there */
-                       DEBUG3("Page %Lu is at %lu\n", (unsigned long long)mapcnt,
+                       DEBUG3("Page %llu is at %lu\n", (unsigned long long)mapcnt,
                               (unsigned long)(client->difmap[mapcnt])) ;
                        myseek(client->difffile,
                                        client->difmap[mapcnt]*DIFFPAGESIZE+offset);
@@ -996,7 +1043,7 @@ int expwrite(off_t a, char *buf, size_t len, CLIENT *client) {
                } else { /* the block is not there */
                        myseek(client->difffile,client->difffilelen*DIFFPAGESIZE) ;
                        client->difmap[mapcnt]=(client->server->flags&F_SPARSE)?mapcnt:client->difffilelen++;
-                       DEBUG3("Page %Lu is not here, we put it at %lu\n",
+                       DEBUG3("Page %llu is not here, we put it at %lu\n",
                               (unsigned long long)mapcnt,
                               (unsigned long)(client->difmap[mapcnt]));
                        rdlen=DIFFPAGESIZE ;
@@ -1018,10 +1065,11 @@ int expwrite(off_t a, char *buf, size_t len, CLIENT *client) {
  * @param client The client we're negotiating with.
  **/
 void negotiate(CLIENT *client) {
-       char zeros[300];
+       char zeros[128];
        u64 size_host;
+       u32 flags = NBD_FLAG_HAS_FLAGS;
 
-       memset(zeros, '\0', 290);
+       memset(zeros, '\0', sizeof(zeros));
        if (write(client->net, INIT_PASSWD, 8) < 0)
                err("Negotiation failed: %m");
        cliserv_magic = htonll(cliserv_magic);
@@ -1030,14 +1078,19 @@ void negotiate(CLIENT *client) {
        size_host = htonll((u64)(client->exportsize));
        if (write(client->net, &size_host, 8) < 0)
                err("Negotiation failed: %m");
-       if (write(client->net, zeros, 128) < 0)
+       if (client->server->flags & F_READONLY)
+               flags |= NBD_FLAG_READ_ONLY;
+       flags = htonl(flags);
+       if (write(client->net, &flags, 4) < 0)
+               err("Negotiation failed: %m");
+       if (write(client->net, zeros, 124) < 0)
                err("Negotiation failed: %m");
 }
 
 /** sending macro. */
 #define SEND(net,reply) writeit( net, &reply, sizeof( reply ));
 /** error macro. */
-#define ERROR(client,reply) { reply.error = htonl(-1); SEND(client->net,reply); reply.error = 0; }
+#define ERROR(client,reply,errcode) { reply.error = htonl(errcode); SEND(client->net,reply); reply.error = 0; }
 /**
  * Serve a file to a single client.
  *
@@ -1045,7 +1098,7 @@ void negotiate(CLIENT *client) {
  * pieces. Preferably with a chainsaw.
  *
  * @param client The client we're going to serve to.
- * @return never
+ * @return when the client disconnects
  **/
 int mainloop(CLIENT *client) {
        struct nbd_request request;
@@ -1065,8 +1118,6 @@ int mainloop(CLIENT *client) {
                i++;
                printf("%d: ", i);
 #endif
-               if (client->server->timeout) 
-                       alarm(client->server->timeout);
                readit(client->net, &request, sizeof(request));
                request.from = ntohll(request.from);
                request.type = ntohl(request.type);
@@ -1090,20 +1141,20 @@ int mainloop(CLIENT *client) {
                if (len > BUFSIZE + sizeof(struct nbd_reply))
                        err("Request too big!");
 #ifdef DODBG
-               printf("%s from %Lu (%Lu) len %d, ", request.type ? "WRITE" :
+               printf("%s from %llu (%llu) len %d, ", request.type ? "WRITE" :
                                "READ", (unsigned long long)request.from,
                                (unsigned long long)request.from / 512, len);
 #endif
                memcpy(reply.handle, request.handle, sizeof(reply.handle));
                if ((request.from + len) > (OFFT_MAX)) {
                        DEBUG("[Number too large!]");
-                       ERROR(client, reply);
+                       ERROR(client, reply, EINVAL);
                        continue;
                }
 
                if (((ssize_t)((off_t)request.from + len) > client->exportsize)) {
                        DEBUG("[RANGE!]");
-                       ERROR(client, reply);
+                       ERROR(client, reply, EINVAL);
                        continue;
                }
 
@@ -1114,12 +1165,12 @@ int mainloop(CLIENT *client) {
                        if ((client->server->flags & F_READONLY) ||
                            (client->server->flags & F_AUTOREADONLY)) {
                                DEBUG("[WRITE to READONLY!]");
-                               ERROR(client, reply);
+                               ERROR(client, reply, EPERM);
                                continue;
                        }
                        if (expwrite(request.from, buf, len, client)) {
                                DEBUG("Write failed: %m" );
-                               ERROR(client, reply);
+                               ERROR(client, reply, errno);
                                continue;
                        }
                        SEND(client->net, reply);
@@ -1131,7 +1182,7 @@ int mainloop(CLIENT *client) {
                DEBUG("exp->buf, ");
                if (expread(request.from, buf + sizeof(struct nbd_reply), len, client)) {
                        DEBUG("Read failed: %m");
-                       ERROR(client, reply);
+                       ERROR(client, reply, errno);
                        continue;
                }
 
@@ -1161,6 +1212,7 @@ void setupexport(CLIENT* client) {
        for(i=0; ; i++) {
                FILE_INFO fi;
                gchar *tmpname;
+               gchar* error_string;
                mode_t mode = (client->server->flags & F_READONLY) ? O_RDONLY : O_RDWR;
 
                if(multifile) {
@@ -1174,14 +1226,21 @@ void setupexport(CLIENT* client) {
                        /* Try again because maybe media was read-only */
                        fi.fhandle = open(tmpname, O_RDONLY);
                        if(fi.fhandle != -1) {
-                               client->server->flags |= F_AUTOREADONLY;
-                               client->server->flags |= F_READONLY;
+                               /* Opening the base file in copyonwrite mode is
+                                * okay */
+                               if(!(client->server->flags & F_COPYONWRITE)) {
+                                       client->server->flags |= F_AUTOREADONLY;
+                                       client->server->flags |= F_READONLY;
+                               }
                        }
                }
                if(fi.fhandle == -1) {
                        if(multifile && i>0)
                                break;
-                       err("Could not open exported file: %m");
+                       error_string=g_strdup_printf(
+                               "Could not open exported file %s: %%m",
+                               tmpname);
+                       err(error_string);
                }
                fi.startoff = laststartoff + lastsize;
                g_array_append_val(client->export, fi);
@@ -1209,7 +1268,7 @@ void setupexport(CLIENT* client) {
                client->exportsize = client->server->expected_size;
        }
 
-       msg3(LOG_INFO, "Size of exported file/device is %Lu", (unsigned long long)client->exportsize);
+       msg3(LOG_INFO, "Size of exported file/device is %llu", (unsigned long long)client->exportsize);
        if(multifile) {
                msg3(LOG_INFO, "Total number of files: %d", i);
        }
@@ -1233,6 +1292,25 @@ int copyonwrite_prepare(CLIENT* client) {
 }
 
 /**
+ * Run a command. This is used for the ``prerun'' and ``postrun'' config file
+ * options
+ *
+ * @param command the command to be ran. Read from the config file
+ * @param file the file name we're about to export
+ **/
+int do_run(gchar* command, gchar* file) {
+       gchar* cmd;
+       int retval=0;
+
+       if(command && *command) {
+               cmd = g_strdup_printf(command, file);
+               retval=system(cmd);
+               g_free(cmd);
+       }
+       return retval;
+}
+
+/**
  * Serve a connection. 
  *
  * @todo allow for multithreading, perhaps use libevent. Not just yet, though;
@@ -1241,6 +1319,9 @@ int copyonwrite_prepare(CLIENT* client) {
  * @param client a connected client
  **/
 void serveconnection(CLIENT *client) {
+       if(do_run(client->server->prerun, client->exportname)) {
+               exit(EXIT_FAILURE);
+       }
        setupexport(client);
 
        if (client->server->flags & F_COPYONWRITE) {
@@ -1250,6 +1331,7 @@ void serveconnection(CLIENT *client) {
        setmysockopt(client->net);
 
        mainloop(client);
+       do_run(client->server->postrun, client->exportname);
 }
 
 /**
@@ -1313,109 +1395,7 @@ void destroy_pid_t(gpointer data) {
 }
 
 /**
- * Go daemon (unless we specified at compile time that we didn't want this)
- * @param serve the first server of our configuration. If its port is zero,
- *     then do not daemonize, because we're doing inetd then. This parameter
- *     is only used to create a PID file of the form
- *     /var/run/nbd-server.&lt;port&gt;.pid; it's not modified in any way.
- **/
-#if !defined(NODAEMON) && !defined(NOFORK)
-void daemonize(SERVER* serve) {
-       FILE*pidf;
-
-       if(daemon(0,0)<0) {
-               err("daemon");
-       }
-       if(!*pidftemplate) {
-               if(serve) {
-                       strncpy(pidftemplate, "/var/run/server.%d.pid", 255);
-               } else {
-                       strncpy(pidftemplate, "/var/run/server.pid", 255);
-               }
-       }
-       snprintf(pidfname, 255, pidftemplate, serve ? serve->port : 0);
-       pidf=fopen(pidfname, "w");
-       if(pidf) {
-               fprintf(pidf,"%d\n", (int)getpid());
-               fclose(pidf);
-       } else {
-               perror("fopen");
-               fprintf(stderr, "Not fatal; continuing");
-       }
-}
-#else
-#define daemonize(serve)
-#endif /* !defined(NODAEMON) && !defined(NOFORK) */
-
-/**
- * Connect a server's socket.
- *
- * @param serve the server we want to connect.
- **/
-void setup_serve(SERVER *serve) {
-       struct sockaddr_in addrin;
-       struct sigaction sa;
-       int addrinlen = sizeof(addrin);
-       int sock_flags;
-#ifndef sun
-       int yes=1;
-#else
-       char yes='1';
-#endif /* sun */
-       if ((serve->socket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0)
-               err("socket: %m");
-
-       /* lose the pesky "Address already in use" error message */
-       if (setsockopt(serve->socket,SOL_SOCKET,SO_REUSEADDR,&yes,sizeof(int)) == -1) {
-               err("setsockopt SO_REUSEADDR");
-       }
-       if (setsockopt(serve->socket,SOL_SOCKET,SO_KEEPALIVE,&yes,sizeof(int)) == -1) {
-               err("setsockopt SO_KEEPALIVE");
-       }
-
-       /* make the listening socket non-blocking */
-       if ((sock_flags = fcntl(serve->socket, F_GETFL, 0)) == -1) {
-               err("fcntl F_GETFL");
-       }
-       if (fcntl(serve->socket, F_SETFL, sock_flags | O_NONBLOCK) == -1) {
-               err("fcntl F_SETFL O_NONBLOCK");
-       }
-
-       DEBUG("Waiting for connections... bind, ");
-       addrin.sin_family = AF_INET;
-       addrin.sin_port = htons(serve->port);
-       addrin.sin_addr.s_addr = 0;
-       if (bind(serve->socket, (struct sockaddr *) &addrin, addrinlen) < 0)
-               err("bind: %m");
-       DEBUG("listen, ");
-       if (listen(serve->socket, 1) < 0)
-               err("listen: %m");
-       sa.sa_handler = sigchld_handler;
-       sigemptyset(&sa.sa_mask);
-       sa.sa_flags = SA_RESTART;
-       if(sigaction(SIGCHLD, &sa, NULL) == -1)
-               err("sigaction: %m");
-       sa.sa_handler = sigterm_handler;
-       sigemptyset(&sa.sa_mask);
-       sa.sa_flags = SA_RESTART;
-       if(sigaction(SIGTERM, &sa, NULL) == -1)
-               err("sigaction: %m");
-}
-
-/**
- * Connect our servers.
- **/
-void setup_servers(GArray* servers) {
-       int i;
-
-       for(i=0;i<servers->len;i++) {
-               setup_serve(&(g_array_index(servers, SERVER, i)));
-       }
-       children=g_hash_table_new_full(g_int_hash, g_int_equal, NULL, destroy_pid_t);
-}
-
-/**
- * Loop through the available servers, and serve them.
+ * Loop through the available servers, and serve them. Never returns.
  **/
 int serveloop(GArray* servers) {
        struct sockaddr_in addrin;
@@ -1426,7 +1406,6 @@ int serveloop(GArray* servers) {
        int sock;
        fd_set mset;
        fd_set rset;
-       struct timeval tv;
 
        /* 
         * Set up the master fd_set. The set of descriptors we need
@@ -1448,16 +1427,21 @@ int serveloop(GArray* servers) {
                pid_t *pid;
 
                memcpy(&rset, &mset, sizeof(fd_set));
-               tv.tv_sec=0;
-               tv.tv_usec=500;
-               if(select(max+1, &rset, NULL, NULL, &tv)>0) {
+               if(select(max+1, &rset, NULL, NULL, NULL)>0) {
                        DEBUG("accept, ");
                        for(i=0;i<servers->len;i++) {
                                serve=&(g_array_index(servers, SERVER, i));
                                if(FD_ISSET(serve->socket, &rset)) {
+                                       int sock_flags;
                                        if ((net=accept(serve->socket, (struct sockaddr *) &addrin, &addrinlen)) < 0)
                                                err("accept: %m");
 
+                                       if((sock_flags = fcntl(net, F_GETFL, 0))==-1) {
+                                               err("fcntl F_GETFL");
+                                       }
+                                       if(fcntl(net, F_SETFL, sock_flags &~O_NONBLOCK)==-1) {
+                                               err("fcntl F_SETFL ~O_NONBLOCK");
+                                       }
                                        client = g_malloc(sizeof(CLIENT));
                                        client->server=serve;
                                        client->exportsize=OFFT_MAX;
@@ -1483,7 +1467,8 @@ int serveloop(GArray* servers) {
                                        }
                                        /* child */
                                        g_hash_table_destroy(children);
-                                       for(i=0;i<servers->len,serve=(g_array_index(servers, SERVER*, i));i++) {
+                                       for(i=0;i<servers->len;i++) {
+                                               serve=&g_array_index(servers, SERVER, i);
                                                close(serve->socket);
                                        }
                                        /* FALSE does not free the
@@ -1496,6 +1481,7 @@ int serveloop(GArray* servers) {
 #endif // NOFORK
                                        msg2(LOG_INFO,"Starting to serve");
                                        serveconnection(client);
+                                       exit(EXIT_SUCCESS);
                                }
                        }
                }
@@ -1503,23 +1489,196 @@ int serveloop(GArray* servers) {
 }
 
 /**
+ * Connect a server's socket.
+ *
+ * @param serve the server we want to connect.
+ **/
+void setup_serve(SERVER *serve) {
+       struct sockaddr_in addrin;
+       struct sigaction sa;
+       int addrinlen = sizeof(addrin);
+       int sock_flags;
+       int af;
+#ifndef sun
+       int yes=1;
+#else
+       char yes='1';
+#endif /* sun */
+
+       af = AF_INET;
+#ifdef WITH_SDP
+       if ((serve->flags) && F_SDP) {
+               af = AF_INET_SDP;
+       }
+#endif
+       if ((serve->socket = socket(af, SOCK_STREAM, IPPROTO_TCP)) < 0)
+               err("socket: %m");
+
+       /* lose the pesky "Address already in use" error message */
+       if (setsockopt(serve->socket,SOL_SOCKET,SO_REUSEADDR,&yes,sizeof(int)) == -1) {
+               err("setsockopt SO_REUSEADDR");
+       }
+       if (setsockopt(serve->socket,SOL_SOCKET,SO_KEEPALIVE,&yes,sizeof(int)) == -1) {
+               err("setsockopt SO_KEEPALIVE");
+       }
+
+       /* make the listening socket non-blocking */
+       if ((sock_flags = fcntl(serve->socket, F_GETFL, 0)) == -1) {
+               err("fcntl F_GETFL");
+       }
+       if (fcntl(serve->socket, F_SETFL, sock_flags | O_NONBLOCK) == -1) {
+               err("fcntl F_SETFL O_NONBLOCK");
+       }
+
+       DEBUG("Waiting for connections... bind, ");
+       addrin.sin_family = AF_INET;
+#ifdef WITH_SDP
+       if(serve->flags & F_SDP) {
+               addrin.sin_family = AF_INET_SDP;
+       }
+#endif
+       addrin.sin_port = htons(serve->port);
+       if(!inet_aton(serve->listenaddr, &(addrin.sin_addr)))
+               err("could not parse listen address");
+       if (bind(serve->socket, (struct sockaddr *) &addrin, addrinlen) < 0)
+               err("bind: %m");
+       DEBUG("listen, ");
+       if (listen(serve->socket, 1) < 0)
+               err("listen: %m");
+       sa.sa_handler = sigchld_handler;
+       sigemptyset(&sa.sa_mask);
+       sa.sa_flags = SA_RESTART;
+       if(sigaction(SIGCHLD, &sa, NULL) == -1)
+               err("sigaction: %m");
+       sa.sa_handler = sigterm_handler;
+       sigemptyset(&sa.sa_mask);
+       sa.sa_flags = SA_RESTART;
+       if(sigaction(SIGTERM, &sa, NULL) == -1)
+               err("sigaction: %m");
+}
+
+/**
+ * Connect our servers.
+ **/
+void setup_servers(GArray* servers) {
+       int i;
+
+       for(i=0;i<servers->len;i++) {
+               setup_serve(&(g_array_index(servers, SERVER, i)));
+       }
+       children=g_hash_table_new_full(g_int_hash, g_int_equal, NULL, destroy_pid_t);
+}
+
+/**
+ * Go daemon (unless we specified at compile time that we didn't want this)
+ * @param serve the first server of our configuration. If its port is zero,
+ *     then do not daemonize, because we're doing inetd then. This parameter
+ *     is only used to create a PID file of the form
+ *     /var/run/nbd-server.&lt;port&gt;.pid; it's not modified in any way.
+ **/
+#if !defined(NODAEMON) && !defined(NOFORK)
+void daemonize(SERVER* serve) {
+       FILE*pidf;
+
+       if(serve && !(serve->port)) {
+               return;
+       }
+       if(daemon(0,0)<0) {
+               err("daemon");
+       }
+       if(!*pidftemplate) {
+               if(serve) {
+                       strncpy(pidftemplate, "/var/run/nbd-server.%d.pid", 255);
+               } else {
+                       strncpy(pidftemplate, "/var/run/nbd-server.pid", 255);
+               }
+       }
+       snprintf(pidfname, 255, pidftemplate, serve ? serve->port : 0);
+       pidf=fopen(pidfname, "w");
+       if(pidf) {
+               fprintf(pidf,"%d\n", (int)getpid());
+               fclose(pidf);
+       } else {
+               perror("fopen");
+               fprintf(stderr, "Not fatal; continuing");
+       }
+}
+#else
+#define daemonize(serve)
+#endif /* !defined(NODAEMON) && !defined(NOFORK) */
+
+/*
+ * Everything beyond this point (in the file) is run in non-daemon mode.
+ * The stuff above daemonize() isn't.
+ */
+
+void serve_err(SERVER* serve, const char* msg) G_GNUC_NORETURN;
+
+void serve_err(SERVER* serve, const char* msg) {
+       g_message("Export of %s on port %d failed:", serve->exportname,
+                       serve->port);
+       err(msg);
+}
+
+/**
  * Set up user-ID and/or group-ID
  **/
 void dousers(void) {
        struct passwd *pw;
        struct group *gr;
-       if(runuser) {
-               pw=getpwnam(runuser);
-               if(setuid(pw->pw_uid)<0)
-                       msg3(LOG_DEBUG, "Could not set UID: %s", strerror(errno));
-       }
        if(rungroup) {
                gr=getgrnam(rungroup);
-               if(setgid(gr->gr_gid)<0)
-                       msg3(LOG_DEBUG, "Could not set GID: %s", strerror(errno));
+               if(!gr) {
+                       g_message("Invalid group name: %s", rungroup);
+                       exit(EXIT_FAILURE);
+               }
+               if(setgid(gr->gr_gid)<0) {
+                       g_message("Could not set GID: %s", strerror(errno));
+                       exit(EXIT_FAILURE);
+               }
+       }
+       if(runuser) {
+               pw=getpwnam(runuser);
+               if(!pw) {
+                       g_message("Invalid user name: %s", runuser);
+                       exit(EXIT_FAILURE);
+               }
+               if(setuid(pw->pw_uid)<0) {
+                       g_message("Could not set UID: %s", strerror(errno));
+                       exit(EXIT_FAILURE);
+               }
        }
 }
 
+#ifndef ISSERVER
+void glib_message_syslog_redirect(const gchar *log_domain,
+                                  GLogLevelFlags log_level,
+                                  const gchar *message,
+                                  gpointer user_data)
+{
+    int level=LOG_DEBUG;
+    
+    switch( log_level )
+    {
+      case G_LOG_FLAG_FATAL:
+      case G_LOG_LEVEL_CRITICAL:
+      case G_LOG_LEVEL_ERROR:    
+        level=LOG_ERR; 
+        break;
+      case G_LOG_LEVEL_WARNING:
+        level=LOG_WARNING;
+        break;
+      case G_LOG_LEVEL_MESSAGE:
+      case G_LOG_LEVEL_INFO:
+        level=LOG_INFO;
+        break;
+      case G_LOG_LEVEL_DEBUG:
+        level=LOG_DEBUG;
+    }
+    syslog(level, message);
+}
+#endif
+
 /**
  * Main entry point...
  **/
@@ -1530,7 +1689,7 @@ int main(int argc, char *argv[]) {
 
        if (sizeof( struct nbd_request )!=28) {
                fprintf(stderr,"Bad size of structure. Alignment problems?\n");
-               exit(-1) ;
+               exit(EXIT_FAILURE) ;
        }
 
        memset(pidftemplate, '\0', 256);
@@ -1539,36 +1698,38 @@ int main(int argc, char *argv[]) {
        config_file_pos = g_strdup(CFILE);
        serve=cmdline(argc, argv);
        servers = parse_cfile(config_file_pos, &err);
-       if(!servers || !servers->len) {
-               g_warning("Could not parse config file: %s", err->message);
-       }
+       
        if(serve) {
                g_array_append_val(servers, *serve);
-       }
-
-/* We don't support this at this time */
-#if 0
-       if (!(serve->port)) {
-               CLIENT *client;
+     
+               if (!(serve->port)) {
+                       CLIENT *client;
 #ifndef ISSERVER
-               /* You really should define ISSERVER if you're going to use
-                * inetd mode, but if you don't, closing stdout and stderr
-                * (which inetd had connected to the client socket) will let it
-                * work. */
-               close(1);
-               close(2);
-               open("/dev/null", O_WRONLY);
-               open("/dev/null", O_WRONLY);
-#endif
-               client=g_malloc(sizeof(CLIENT));
-               client->server=serve;
-               client->net=0;
-               client->exportsize=OFFT_MAX;
-               set_peername(0,client);
-               serveconnection(client);
-               return 0;
-        }
+                       /* You really should define ISSERVER if you're going to use
+                        * inetd mode, but if you don't, closing stdout and stderr
+                        * (which inetd had connected to the client socket) will let it
+                        * work. */
+                       close(1);
+                       close(2);
+                       open("/dev/null", O_WRONLY);
+                       open("/dev/null", O_WRONLY);
+                       g_log_set_default_handler( glib_message_syslog_redirect, NULL );
 #endif
+                       client=g_malloc(sizeof(CLIENT));
+                       client->server=serve;
+                       client->net=0;
+                       client->exportsize=OFFT_MAX;
+                       set_peername(0,client);
+                       serveconnection(client);
+                       return 0;
+               }
+       }
+    
+    if(!servers || !servers->len) {
+               g_warning("Could not parse config file: %s", 
+                               err ? err->message : "Unknown error");
+       }
+    
        if((!serve) && (!servers||!servers->len)) {
                g_message("Nothing to do! Bye!");
                exit(EXIT_FAILURE);