X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~mdw/git/disorder/blobdiff_plain/c4e2cfdd2d1eabe3d556fb7a5938eca465f9c249..eb5e067336c457058b5e67bf5835b778ec100019:/lib/client.c diff --git a/lib/client.c b/lib/client.c index 0c12c90..84eb77e 100644 --- a/lib/client.c +++ b/lib/client.c @@ -1,6 +1,6 @@ /* * This file is part of DisOrder. - * Copyright (C) 2004, 2005, 2006, 2007 Richard Kettlewell + * Copyright (C) 2004-2008 Richard Kettlewell * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -20,23 +20,19 @@ /** @file lib/client.c * @brief Simple C client * - * See @file lib/eclient.c for an asynchronous-capable client + * See @ref lib/eclient.c for an asynchronous-capable client * implementation. */ -#include -#include "types.h" +#include "common.h" #include #include #include #include -#include -#include #include #include #include -#include #include #include "log.h" @@ -58,27 +54,31 @@ #include "client-common.h" #include "rights.h" #include "trackdb.h" +#include "kvp.h" +/** @brief Client handle contents */ struct disorder_client { - FILE *fpin, *fpout; + /** @brief Stream to read from */ + FILE *fpin; + /** @brief Stream to write to */ + FILE *fpout; + /** @brief Peer description */ char *ident; + /** @brief Username */ char *user; + /** @brief Report errors to @c stderr */ int verbose; + /** @brief Last error string */ + const char *last; }; -static int disorder_connect_sock(disorder_client *c, - const struct sockaddr *sa, - socklen_t len, - const char *username, - const char *password, - const char *ident); - /** @brief Create a new client * @param verbose If nonzero, write extra junk to stderr * @return Pointer to new client * - * You must call disorder_connect() to connect it. Use - * disorder_close() to dispose of the client when finished with it. + * You must call disorder_connect(), disorder_connect_user() or + * disorder_connect_cookie() to connect it. Use disorder_close() to + * dispose of the client when finished with it. */ disorder_client *disorder_new(int verbose) { disorder_client *c = xmalloc(sizeof (struct disorder_client)); @@ -95,22 +95,34 @@ disorder_client *disorder_new(int verbose) { static int response(disorder_client *c, char **rp) { char *r; - if(inputline(c->ident, c->fpin, &r, '\n')) + if(inputline(c->ident, c->fpin, &r, '\n')) { + byte_xasprintf((char **)&c->last, "input error: %s", strerror(errno)); return -1; + } D(("response: %s", r)); if(rp) *rp = r; if(r[0] >= '0' && r[0] <= '9' && r[1] >= '0' && r[1] <= '9' && r[2] >= '0' && r[2] <= '9' - && r[3] == ' ') + && r[3] == ' ') { + c->last = r + 4; return (r[0] * 10 + r[1]) * 10 + r[2] - 111 * '0'; - else { + } else { + c->last = "invalid reply format"; error(0, "invalid reply format from %s", c->ident); return -1; } } +/** @brief Return last response string + * @param c Client + * @return Last response string (UTF-8, English) or NULL + */ +const char *disorder_last(disorder_client *c) { + return c->last; +} + /** @brief Read and partially parse a response * @param c Client * @param rp Where to store response text (or NULL) (UTF-8) @@ -136,7 +148,7 @@ static int check_response(disorder_client *c, char **rp) { } else { if(c->verbose) error(0, "from %s: %s", c->ident, utf82mb(r)); - return -1; + return rc; } } @@ -161,6 +173,11 @@ static int disorder_simple_v(disorder_client *c, const char *arg; struct dynstr d; + if(!c->fpout) { + c->last = "not connected"; + error(0, "not connected to server"); + return -1; + } if(cmd) { dynstr_init(&d); dynstr_append_string(&d, cmd); @@ -172,6 +189,7 @@ static int disorder_simple_v(disorder_client *c, dynstr_terminate(&d); D(("command: %s", d.vec)); if(fputs(d.vec, c->fpout) < 0 || fflush(c->fpout)) { + byte_xasprintf((char **)&c->last, "write error: %s", strerror(errno)); error(errno, "error writing to %s", c->ident); return -1; } @@ -208,114 +226,200 @@ static int disorder_simple(disorder_client *c, return ret; } -static int connect_sock(void *vc, - const struct sockaddr *sa, - socklen_t len, - const char *ident) { - const char *username, *password; - disorder_client *c = vc; - - if(!(username = config->username)) { - error(0, "no username configured"); - return -1; - } - password = config->password; - if(!password) { - /* Maybe we can read the database */ - /* TODO failure to open the database should not be fatal */ - trackdb_init(TRACKDB_NO_RECOVER|TRACKDB_NO_UPGRADE); - trackdb_open(TRACKDB_READ_ONLY); - password = trackdb_get_password(username); - trackdb_close(); - } - if(!password) { - /* Oh well */ - error(0, "no password configured"); - return -1; +/** @brief Dequote a result string + * @param rc 0 on success, non-0 on error + * @param rp Where result string is stored (UTF-8) + * @return @p rc + * + * This is used as a wrapper around disorder_simple() to dequote + * results in place. + */ +static int dequote(int rc, char **rp) { + char **rr; + + if(!rc) { + if((rr = split(*rp, 0, SPLIT_QUOTES, 0, 0)) && *rr) { + *rp = *rr; + return 0; + } + error(0, "invalid reply: %s", *rp); } - return disorder_connect_sock(c, sa, len, username, password, ident); + return rc; } -/** @brief Connect a client +/** @brief Generic connection routine * @param c Client + * @param username Username to log in with or NULL + * @param password Password to log in with or NULL + * @param cookie Cookie to log in with or NULL * @return 0 on success, non-0 on error * - * The connection will use the username and password found in @ref - * config. + * @p cookie is tried first if not NULL. If it is NULL then @p + * username must not be. If @p username is not NULL then nor may @p + * password be. */ -int disorder_connect(disorder_client *c) { - return with_sockaddr(c, connect_sock); -} - -static int disorder_connect_sock(disorder_client *c, - const struct sockaddr *sa, - socklen_t len, - const char *username, - const char *password, - const char *ident) { - int fd = -1, fd2 = -1, nrvec; +static int disorder_connect_generic(disorder_client *c, + const char *username, + const char *password, + const char *cookie) { + int fd = -1, fd2 = -1, nrvec, rc; unsigned char *nonce; size_t nl; const char *res; char *r, **rvec; const char *protocol, *algorithm, *challenge; + struct sockaddr *sa; + socklen_t salen; - if(!password) { - error(0, "no password found"); + if((salen = find_server(&sa, &c->ident)) == (socklen_t)-1) return -1; - } c->fpin = c->fpout = 0; if((fd = socket(sa->sa_family, SOCK_STREAM, 0)) < 0) { + byte_xasprintf((char **)&c->last, "socket: %s", strerror(errno)); error(errno, "error calling socket"); return -1; } - if(connect(fd, sa, len) < 0) { + if(connect(fd, sa, salen) < 0) { + byte_xasprintf((char **)&c->last, "connect: %s", strerror(errno)); error(errno, "error calling connect"); goto error; } if((fd2 = dup(fd)) < 0) { + byte_xasprintf((char **)&c->last, "dup: %s", strerror(errno)); error(errno, "error calling dup"); goto error; } if(!(c->fpin = fdopen(fd, "rb"))) { + byte_xasprintf((char **)&c->last, "fdopen: %s", strerror(errno)); error(errno, "error calling fdopen"); goto error; } fd = -1; if(!(c->fpout = fdopen(fd2, "wb"))) { + byte_xasprintf((char **)&c->last, "fdopen: %s", strerror(errno)); error(errno, "error calling fdopen"); goto error; } fd2 = -1; - c->ident = xstrdup(ident); - if(disorder_simple(c, &r, 0, (const char *)0)) - return -1; + if((rc = disorder_simple(c, &r, 0, (const char *)0))) + goto error_rc; if(!(rvec = split(r, &nrvec, SPLIT_QUOTES, 0, 0))) - return -1; + goto error; if(nrvec != 3) { + c->last = "cannot parse server greeting"; error(0, "cannot parse server greeting %s", r); - return -1; + goto error; } protocol = *rvec++; if(strcmp(protocol, "2")) { + c->last = "unknown protocol version"; error(0, "unknown protocol version: %s", protocol); - return -1; + goto error; } algorithm = *rvec++; challenge = *rvec++; if(!(nonce = unhex(challenge, &nl))) - return -1; - if(!(res = authhash(nonce, nl, password, algorithm))) goto error; - if(disorder_simple(c, 0, "user", username, res, (char *)0)) - return -1; + goto error; + if(cookie) { + if(!dequote(disorder_simple(c, &c->user, "cookie", cookie, (char *)0), + &c->user)) + return 0; /* success */ + if(!username) { + c->last = "cookie failed and no username"; + error(0, "cookie did not work and no username available"); + goto error; + } + } + if(!(res = authhash(nonce, nl, password, algorithm))) { + c->last = "error computing authorization hash"; + goto error; + } + if((rc = disorder_simple(c, 0, "user", username, res, (char *)0))) + goto error_rc; c->user = xstrdup(username); return 0; error: - if(c->fpin) fclose(c->fpin); - if(c->fpout) fclose(c->fpout); + rc = -1; +error_rc: + if(c->fpin) { + fclose(c->fpin); + c->fpin = 0; + } + if(c->fpout) { + fclose(c->fpout); + c->fpout = 0; + } if(fd2 != -1) close(fd2); if(fd != -1) close(fd); - return -1; + return rc; +} + +/** @brief Connect a client with a specified username and password + * @param c Client + * @param username Username to log in with + * @param password Password to log in with + * @return 0 on success, non-0 on error + */ +int disorder_connect_user(disorder_client *c, + const char *username, + const char *password) { + return disorder_connect_generic(c, + username, + password, + 0); +} + +/** @brief Connect a client + * @param c Client + * @return 0 on success, non-0 on error + * + * The connection will use the username and password found in @ref + * config, or directly from the database if no password is found and + * the database is readable (usually only for root). + */ +int disorder_connect(disorder_client *c) { + const char *username, *password; + + if(!(username = config->username)) { + c->last = "no username"; + error(0, "no username configured"); + return -1; + } + password = config->password; + /* Maybe we can read the database */ + if(!password && trackdb_readable()) { + trackdb_init(TRACKDB_NO_RECOVER|TRACKDB_NO_UPGRADE); + trackdb_open(TRACKDB_READ_ONLY); + password = trackdb_get_password(username); + trackdb_close(); + } + if(!password) { + /* Oh well */ + c->last = "no password"; + error(0, "no password configured"); + return -1; + } + return disorder_connect_generic(c, + username, + password, + 0); +} + +/** @brief Connect a client + * @param c Client + * @param cookie Cookie to log in with, or NULL + * @return 0 on success, non-0 on error + * + * If @p cookie is NULL or does not work then we attempt to log in as + * guest instead (so when the cookie expires only an extra round trip + * is needed rathre than a complete new login). + */ +int disorder_connect_cookie(disorder_client *c, + const char *cookie) { + return disorder_connect_generic(c, + "guest", + "", + cookie); } /** @brief Close a client @@ -330,6 +434,7 @@ int disorder_close(disorder_client *c) { if(c->fpin) { if(fclose(c->fpin) < 0) { + byte_xasprintf((char **)&c->last, "fclose: %s", strerror(errno)); error(errno, "error calling fclose"); ret = -1; } @@ -337,17 +442,14 @@ int disorder_close(disorder_client *c) { } if(c->fpout) { if(fclose(c->fpout) < 0) { + byte_xasprintf((char **)&c->last, "fclose: %s", strerror(errno)); error(errno, "error calling fclose"); ret = -1; } c->fpout = 0; } - return 0; -} - -int disorder_become(disorder_client *c, const char *user) { - if(disorder_simple(c, 0, "become", user, (char *)0)) return -1; - c->user = xstrdup(user); + c->ident = 0; + c->user = 0; return 0; } @@ -431,26 +533,6 @@ int disorder_rescan(disorder_client *c) { return disorder_simple(c, 0, "rescan", (char *)0); } -/** @brief Dequote a result string - * @param rc 0 on success, non-0 on error - * @param rp Where result string is stored (UTF-8) - * @return @p rc - * - * This is used as a wrapper around disorder_simple() to dequote - * results in place. - */ -static int dequote(int rc, char **rp) { - char **rr; - if(!rc) { - if((rr = split(*rp, 0, SPLIT_QUOTES, 0, 0)) && *rr) { - *rp = *rr; - return 0; - } - error(0, "invalid reply: %s", *rp); - } - return -1; -} - /** @brief Get server version number * @param c Client * @param rp Where to store version string (UTF-8) @@ -475,9 +557,10 @@ static void client_error(const char *msg, int disorder_playing(disorder_client *c, struct queue_entry **qp) { char *r; struct queue_entry *q; + int rc; - if(disorder_simple(c, &r, "playing", (char *)0)) - return -1; + if((rc = disorder_simple(c, &r, "playing", (char *)0))) + return rc; if(r) { q = xmalloc(sizeof *q); if(queue_unmarshall(q, r, client_error, 0)) @@ -488,13 +571,15 @@ int disorder_playing(disorder_client *c, struct queue_entry **qp) { return 0; } +/** @brief Fetch the queue, recent list, etc */ static int disorder_somequeue(disorder_client *c, const char *cmd, struct queue_entry **qp) { struct queue_entry *qh, **qt = &qh, *q; char *l; + int rc; - if(disorder_simple(c, 0, cmd, (char *)0)) - return -1; + if((rc = disorder_simple(c, 0, cmd, (char *)0))) + return rc; while(inputline(c->ident, c->fpin, &l, '\n') >= 0) { if(!strcmp(l, ".")) { *qt = 0; @@ -507,10 +592,13 @@ static int disorder_somequeue(disorder_client *c, qt = &q->next; } } - if(ferror(c->fpin)) + if(ferror(c->fpin)) { + byte_xasprintf((char **)&c->last, "input error: %s", strerror(errno)); error(errno, "error reading %s", c->ident); - else + } else { + c->last = "input error: unexpxected EOF"; error(0, "error reading %s: unexpected EOF", c->ident); + } return -1; } @@ -559,10 +647,13 @@ static int readlist(disorder_client *c, char ***vecp, int *nvecp) { } vector_append(&v, l + (*l == '.')); } - if(ferror(c->fpin)) + if(ferror(c->fpin)) { + byte_xasprintf((char **)&c->last, "input error: %s", strerror(errno)); error(errno, "error reading %s", c->ident); - else + } else { + c->last = "input error: unexpxected EOF"; error(0, "error reading %s: unexpected EOF", c->ident); + } return -1; } @@ -593,7 +684,7 @@ static int disorder_simple_list(disorder_client *c, /** @brief List directories below @p dir * @param c Client - * @param dir Directory to list (UTF-8) + * @param dir Directory to list, or NULL for root (UTF-8) * @param re Regexp that results must match, or NULL (UTF-8) * @param vecp Where to store list (UTF-8) * @param nvecp Where to store number of items, or NULL @@ -606,7 +697,7 @@ int disorder_directories(disorder_client *c, const char *dir, const char *re, /** @brief List files below @p dir * @param c Client - * @param dir Directory to list (UTF-8) + * @param dir Directory to list, or NULL for root (UTF-8) * @param re Regexp that results must match, or NULL (UTF-8) * @param vecp Where to store list (UTF-8) * @param nvecp Where to store number of items, or NULL @@ -619,7 +710,7 @@ int disorder_files(disorder_client *c, const char *dir, const char *re, /** @brief List files and directories below @p dir * @param c Client - * @param dir Directory to list (UTF-8) + * @param dir Directory to list, or NULL for root (UTF-8) * @param re Regexp that results must match, or NULL (UTF-8) * @param vecp Where to store list (UTF-8) * @param nvecp Where to store number of items, or NULL @@ -679,7 +770,7 @@ static void pref_error_handler(const char *msg, error(0, "error handling 'prefs' reply: %s", msg); } -/** @param Get all preferences for a trcak +/** @brief Get all preferences for a trcak * @param c Client * @param track Track name * @param kp Where to store linked list of preferences @@ -687,11 +778,11 @@ static void pref_error_handler(const char *msg, */ int disorder_prefs(disorder_client *c, const char *track, struct kvp **kp) { char **vec, **pvec; - int nvec, npvec, n; + int nvec, npvec, n, rc; struct kvp *k; - if(disorder_simple_list(c, &vec, &nvec, "prefs", track, (char *)0)) - return -1; + if((rc = disorder_simple_list(c, &vec, &nvec, "prefs", track, (char *)0))) + return rc; for(n = 0; n < nvec; ++n) { if(!(pvec = split(vec[n], &npvec, SPLIT_QUOTES, pref_error_handler, 0))) return -1; @@ -733,8 +824,10 @@ static int boolean(const char *cmd, const char *value, */ int disorder_exists(disorder_client *c, const char *track, int *existsp) { char *v; + int rc; - if(disorder_simple(c, &v, "exists", track, (char *)0)) return -1; + if((rc = disorder_simple(c, &v, "exists", track, (char *)0))) + return rc; return boolean("exists", v, existsp); } @@ -745,8 +838,10 @@ int disorder_exists(disorder_client *c, const char *track, int *existsp) { */ int disorder_enabled(disorder_client *c, int *enabledp) { char *v; + int rc; - if(disorder_simple(c, &v, "enabled", (char *)0)) return -1; + if((rc = disorder_simple(c, &v, "enabled", (char *)0))) + return rc; return boolean("enabled", v, enabledp); } @@ -761,8 +856,10 @@ int disorder_enabled(disorder_client *c, int *enabledp) { int disorder_length(disorder_client *c, const char *track, long *valuep) { char *value; + int rc; - if(disorder_simple(c, &value, "length", track, (char *)0)) return -1; + if((rc = disorder_simple(c, &value, "length", track, (char *)0))) + return rc; *valuep = atol(value); return 0; } @@ -797,13 +894,15 @@ int disorder_random_disable(disorder_client *c) { /** @brief Test whether random play is enabled * @param c Client - * @param existsp Where to store result (non-0 iff enabled) + * @param enabledp Where to store result (non-0 iff enabled) * @return 0 on success, non-0 on error */ int disorder_random_enabled(disorder_client *c, int *enabledp) { char *v; + int rc; - if(disorder_simple(c, &v, "random-enabled", (char *)0)) return -1; + if((rc = disorder_simple(c, &v, "random-enabled", (char *)0))) + return rc; return boolean("random-enabled", v, enabledp); } @@ -830,8 +929,7 @@ int disorder_set_volume(disorder_client *c, int left, int right) { if(byte_asprintf(&ls, "%d", left) < 0 || byte_asprintf(&rs, "%d", right) < 0) return -1; - if(disorder_simple(c, 0, "volume", ls, rs, (char *)0)) return -1; - return 0; + return disorder_simple(c, 0, "volume", ls, rs, (char *)0); } /** @brief Get volume @@ -842,9 +940,12 @@ int disorder_set_volume(disorder_client *c, int left, int right) { */ int disorder_get_volume(disorder_client *c, int *left, int *right) { char *r; + int rc; - if(disorder_simple(c, &r, "volume", (char *)0)) return -1; + if((rc = disorder_simple(c, &r, "volume", (char *)0))) + return rc; if(sscanf(r, "%d %d", left, right) != 2) { + c->last = "malformed volume response"; error(0, "error parsing response to 'volume': '%s'", r); return -1; } @@ -858,11 +959,17 @@ int disorder_get_volume(disorder_client *c, int *left, int *right) { */ int disorder_log(disorder_client *c, struct sink *s) { char *l; + int rc; - if(disorder_simple(c, 0, "log", (char *)0)) return -1; + if((rc = disorder_simple(c, 0, "log", (char *)0))) + return rc; while(inputline(c->ident, c->fpin, &l, '\n') >= 0 && strcmp(l, ".")) if(sink_printf(s, "%s\n", l) < 0) return -1; - if(ferror(c->fpin) || feof(c->fpin)) return -1; + if(ferror(c->fpin) || feof(c->fpin)) { + byte_xasprintf((char **)&c->last, "input error: %s", + ferror(c->fpin) ? strerror(errno) : "unexpxected EOF"); + return -1; + } return 0; } @@ -882,7 +989,7 @@ int disorder_part(disorder_client *c, char **partp, /** @brief Resolve aliases * @param c Client - * @param trackkp Where to store canonical name (UTF-8) + * @param trackp Where to store canonical name (UTF-8) * @param track Track name (UTF-8) * @return 0 on success, non-0 on error */ @@ -991,6 +1098,7 @@ int disorder_rtp_address(disorder_client *c, char **addressp, char **portp) { return rc; vec = split(r, &n, SPLIT_QUOTES, 0, 0); if(n != 2) { + c->last = "malformed RTP address"; error(0, "malformed rtp-address reply"); return -1; } @@ -1051,7 +1159,6 @@ int disorder_edituser(disorder_client *c, const char *user, * @param user Username * @param password Password * @param email Email address (UTF-8) - * @param rights Initial rights or NULL to use default * @param confirmp Where to store confirmation string * @return 0 on success, non-0 on error */ @@ -1069,7 +1176,13 @@ int disorder_register(disorder_client *c, const char *user, * @return 0 on success, non-0 on error */ int disorder_confirm(disorder_client *c, const char *confirm) { - return disorder_simple(c, 0, "confirm", confirm, (char *)0); + char *u; + int rc; + + if(!(rc = dequote(disorder_simple(c, &u, "confirm", confirm, (char *)0), + &u))) + c->user = u; + return rc; } /** @brief Make a cookie for this login @@ -1082,6 +1195,111 @@ int disorder_make_cookie(disorder_client *c, char **cookiep) { cookiep); } +/** @brief Revoke the cookie used by this session + * @param c Client + * @return 0 on success, non-0 on error + */ +int disorder_revoke(disorder_client *c) { + return disorder_simple(c, 0, "revoke", (char *)0); +} + +/** @brief Request a password reminder email + * @param c Client + * @param user Username + * @return 0 on success, non-0 on error + */ +int disorder_reminder(disorder_client *c, const char *user) { + return disorder_simple(c, 0, "reminder", user, (char *)0); +} + +/** @brief List scheduled events + * @param c Client + * @param idsp Where to put list of event IDs + * @param nidsp Where to put count of event IDs, or NULL + * @return 0 on success, non-0 on error + */ +int disorder_schedule_list(disorder_client *c, char ***idsp, int *nidsp) { + return disorder_simple_list(c, idsp, nidsp, "schedule-list", (char *)0); +} + +/** @brief Delete a scheduled event + * @param c Client + * @param id Event ID to delete + * @return 0 on success, non-0 on error + */ +int disorder_schedule_del(disorder_client *c, const char *id) { + return disorder_simple(c, 0, "schedule-del", id, (char *)0); +} + +/** @brief Get details of a scheduled event + * @param c Client + * @param id Event ID + * @param actiondatap Where to put details + * @return 0 on success, non-0 on error + */ +int disorder_schedule_get(disorder_client *c, const char *id, + struct kvp **actiondatap) { + char **lines, **bits; + int rc, nbits; + + *actiondatap = 0; + if((rc = disorder_simple_list(c, &lines, NULL, + "schedule-get", id, (char *)0))) + return rc; + while(*lines) { + if(!(bits = split(*lines++, &nbits, SPLIT_QUOTES, 0, 0))) { + error(0, "invalid schedule-get reply: cannot split line"); + return -1; + } + if(nbits != 2) { + error(0, "invalid schedule-get reply: wrong number of fields"); + return -1; + } + kvp_set(actiondatap, bits[0], bits[1]); + } + return 0; +} + +/** @brief Add a scheduled event + * @param c Client + * @param when When to trigger the event + * @param priority Event priority ("normal" or "junk") + * @param action What action to perform + * @param ... Action-specific arguments + * @return 0 on success, non-0 on error + * + * For action @c "play" the next argument is the track. + * + * For action @c "set-global" next argument is the global preference name + * and the final argument the value to set it to, or (char *)0 to unset it. + */ +int disorder_schedule_add(disorder_client *c, + time_t when, + const char *priority, + const char *action, + ...) { + va_list ap; + char when_str[64]; + int rc; + + snprintf(when_str, sizeof when_str, "%lld", (long long)when); + va_start(ap, action); + if(!strcmp(action, "play")) + rc = disorder_simple(c, 0, "schedule-add", when_str, priority, + action, va_arg(ap, char *), + (char *)0); + else if(!strcmp(action, "set-global")) { + const char *key = va_arg(ap, char *); + const char *value = va_arg(ap, char *); + rc = disorder_simple(c, 0,"schedule-add", when_str, priority, + action, key, value, + (char *)0); + } else + fatal(0, "unknown action '%s'", action); + va_end(ap); + return rc; +} + /* Local Variables: c-basic-offset:2