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author | Ludovic Courtès <ludo@gnu.org> | 2010-02-14 20:56:31 +0100 |
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committer | Ludovic Courtès <ludo@gnu.org> | 2010-02-14 20:56:47 +0100 |
commit | 55ae00ea73e5698d64c31118717c15e6dd9cafe7 (patch) | |
tree | 514b45f0da93acaeb3c66b5e75328c479fb6bbc6 /libguile/net_db.c | |
parent | 61cd9dc907b8a09990b14e9aeac7e20fe77cecc6 (diff) | |
download | guile-55ae00ea73e5698d64c31118717c15e6dd9cafe7.tar.gz |
Add `getaddrinfo' and related procedures.
* libguile/net_db.c (sym_getaddrinfo_error, sym_ai_passive,
sym_ai_canonname, sym_ai_numerichost, sym_ai_numericserv,
sym_ai_v4mapped, sym_ai_all, sym_ai_addrconfig, sym_eai_badflags,
sym_eai_noname, sym_eai_again, sym_eai_fail, sym_eai_family,
sym_eai_socktype, sym_eai_service, sym_eai_memory, sym_eai_system,
sym_eai_overflow, sym_eai_nodata, sym_eai_addrfamily,
sym_eai_inprogress, sym_eai_canceled, sym_eai_notcanceled,
sym_eai_alldone, sym_eai_intr, sym_eai_idn_encode): New variables.
(scm_from_addrinfo, scm_getaddrinfo, scm_gai_strerror): New functions.
* libguile/net_db.h (scm_getaddrinfo, scm_gai_strerror): New functions.
* module/ice-9/networking.scm (addrinfo:flags, addrinfo:fam,
addrinfo:socktype, addrinfo:protocol, addrinfo:addr,
addrinfo:canonname): New procedures.
* test-suite/tests/net-db.test: New file.
* test-suite/Makefile.am (SCM_TESTS): Add `tests/net-db.test'.
* doc/ref/posix.texi (Network Databases)[getaddrinfo]: New subsection.
[The Host Database]: Suggest using `getaddrinfo'.
Diffstat (limited to 'libguile/net_db.c')
-rw-r--r-- | libguile/net_db.c | 292 |
1 files changed, 291 insertions, 1 deletions
diff --git a/libguile/net_db.c b/libguile/net_db.c index 4307091f7..ca6dafb28 100644 --- a/libguile/net_db.c +++ b/libguile/net_db.c @@ -30,6 +30,7 @@ # include <config.h> #endif +#include <verify.h> #include <errno.h> #include "libguile/_scm.h" @@ -40,6 +41,7 @@ #include "libguile/validate.h" #include "libguile/net_db.h" +#include "libguile/socket.h" #ifdef HAVE_STRING_H #include <string.h> @@ -449,8 +451,296 @@ SCM_DEFINE (scm_setserv, "setserv", 0, 1, 0, #undef FUNC_NAME #endif + +/* Protocol-independent name resolution with getaddrinfo(3) & co. */ + +SCM_SYMBOL (sym_getaddrinfo_error, "getaddrinfo-error"); + +/* Make sure the `AI_*' flags can be stored as INUMs. */ +verify (SCM_I_INUM (SCM_I_MAKINUM (AI_ALL)) == AI_ALL); + +/* Valid values for the `ai_flags' to `struct addrinfo'. */ +SCM_VARIABLE_INIT (sym_ai_passive, "AI_PASSIVE", + SCM_I_MAKINUM (AI_PASSIVE)); +SCM_VARIABLE_INIT (sym_ai_canonname, "AI_CANONNAME", + SCM_I_MAKINUM (AI_CANONNAME)); +SCM_VARIABLE_INIT (sym_ai_numerichost, "AI_NUMERICHOST", + SCM_I_MAKINUM (AI_NUMERICHOST)); +SCM_VARIABLE_INIT (sym_ai_numericserv, "AI_NUMERICSERV", + SCM_I_MAKINUM (AI_NUMERICSERV)); +SCM_VARIABLE_INIT (sym_ai_v4mapped, "AI_V4MAPPED", + SCM_I_MAKINUM (AI_V4MAPPED)); +SCM_VARIABLE_INIT (sym_ai_all, "AI_ALL", + SCM_I_MAKINUM (AI_ALL)); +SCM_VARIABLE_INIT (sym_ai_addrconfig, "AI_ADDRCONFIG", + SCM_I_MAKINUM (AI_ADDRCONFIG)); + +/* Return a Scheme vector whose elements correspond to the fields of C_AI, + ignoring the `ai_next' field. This function is not exported because the + definition of `struct addrinfo' is provided by Gnulib. */ +static SCM +scm_from_addrinfo (const struct addrinfo *c_ai) +{ + SCM ai; + + /* Note: The indices here must be kept synchronized with those used by the + `addrinfo:' procedures in `networking.scm'. */ + + ai = scm_c_make_vector (6, SCM_UNDEFINED); + SCM_SIMPLE_VECTOR_SET (ai, 0, scm_from_int (c_ai->ai_flags)); + SCM_SIMPLE_VECTOR_SET (ai, 1, scm_from_int (c_ai->ai_family)); + SCM_SIMPLE_VECTOR_SET (ai, 2, scm_from_int (c_ai->ai_socktype)); + SCM_SIMPLE_VECTOR_SET (ai, 3, scm_from_int (c_ai->ai_protocol)); + SCM_SIMPLE_VECTOR_SET (ai, 4, + scm_from_sockaddr (c_ai->ai_addr, c_ai->ai_addrlen)); + SCM_SIMPLE_VECTOR_SET (ai, 5, scm_from_locale_string (c_ai->ai_canonname)); + + return ai; +} + +SCM_DEFINE (scm_getaddrinfo, "getaddrinfo", 1, 5, 0, + (SCM name, SCM service, SCM hint_flags, SCM hint_family, + SCM hint_socktype, SCM hint_protocol), + "Return a list of @code{addrinfo} structures containing " + "a socket address and associated information for host @var{name} " + "and/or @var{service} to be used in creating a socket with " + "which to address the specified service.\n\n" + "@example\n" + "(let* ((ai (car (getaddrinfo \"www.gnu.org\" \"http\")))\n" + " (s (socket (addrinfo:fam ai) (addrinfo:socktype ai)\n" + " (addrinfo:protocol ai))))\n" + " (connect s (addrinfo:addr ai))\n" + " s)\n" + "@end example\n\n" + "When @var{service} is omitted or is @code{#f}, return " + "network-level addresses for @var{name}. When @var{name} " + "is @code{#f} @var{service} must be provided and service " + "locations local to the caller are returned.\n" + "\n" + "Additional hints can be provided. When specified, " + "@var{hint_flags} should be a bitwise-or of zero or more " + "constants among the following:\n\n" + "@table @code\n" + "@item AI_PASSIVE\n" + "Socket address is intended for @code{bind}.\n\n" + "@item AI_CANONNAME\n" + "Request for canonical host name, available via " + "@code{addrinfo:canonname}. This makes sense mainly when " + "DNS lookups are involved.\n\n" + "@item AI_NUMERICHOST\n" + "Specifies that @var{name} is a numeric host address string " + "(e.g., @code{\"127.0.0.1\"}), meaning that name resolution " + "will not be used.\n\n" + "@item AI_NUMERICSERV\n" + "Likewise, specifies that @var{service} is a numeric port " + "string (e.g., @code{\"80\"}).\n\n" + "@item AI_ADDRCONFIG\n" + "Return only addresses configured on the local system. It is " + "highly recommended to provide this flag when the returned " + "socket addresses are to be used to make connections; " + "otherwise, some of the returned addresses could be unreachable " + "or use a protocol that is not supported.\n\n" + "@item AI_V4MAPPED\n" + "When looking up IPv6 addresses, return mapped " + "IPv4 addresses if there is no IPv6 address available at all.\n\n" + "@item AI_ALL\n" + "If this flag is set along with @code{AI_V4MAPPED} when looking " + "up IPv6 addresses, return all IPv6 addresses " + "as well as all IPv4 addresses, the latter mapped to IPv6 " + "format.\n" + "@end table\n\n" + "When given, @var{hint_family} should specify the requested " + "address family, e.g., @code{AF_INET6}. Similarly, " + "@var{hint_socktype} should specify the requested socket type " + "(e.g., @code{SOCK_DGRAM}), and @var{hint_protocol} should " + "specify the requested protocol (its value is interpretered " + "as in calls to @code{socket}).\n" + "\n" + "On error, an exception with key @code{getaddrinfo-error} is " + "thrown, with an error code (an integer) as its argument:\n\n" + "@example\n" + "(catch 'getaddrinfo-error\n" + " (lambda ()\n" + " (getaddrinfo \"www.gnu.org\" \"gopher\"))\n" + " (lambda (key errcode)\n" + " (cond ((= errcode EAI_SERVICE)\n" + " (display \"doesn't know about Gopher!\\n\"))\n" + " ((= errcode EAI_NONAME)\n" + " (display \"www.gnu.org not found\\n\"))\n" + " (else\n" + " (format #t \"something wrong: ~a\\n\"\n" + " (gai-strerror errcode))))))\n" + "@end example\n" + "\n" + "Error codes are:\n\n" + "@table @code\n" + "@item EAI_AGAIN\n" + "The name or service could not be resolved at this time. Future " + "attempts may succeed.\n\n" + "@item EAI_BADFLAGS\n" + "@var{hint_flags} contains an invalid value.\n\n" + "@item EAI_FAIL\n" + "A non-recoverable error occurred when attempting to " + "resolve the name.\n\n" + "@item EAI_FAMILY\n" + "@var{hint_family} was not recognized.\n\n" + "@item EAI_NONAME\n" + "Either @var{name} does not resolve for the supplied parameters, " + "or neither @var{name} nor @var{service} were supplied.\n\n" + "@item EAI_SERVICE\n" + "@var{service} was not recognized for the specified socket type.\n\n" + "@item EAI_SOCKTYPE\n" + "@var{hint_socktype} was not recognized.\n\n" + "@item EAI_SYSTEM\n" + "A system error occurred; the error code can be found in " + "@code{errno}.\n" + "@end table\n" + "\n" + "Users are encouraged to read the " + "@url{http://www.opengroup.org/onlinepubs/9699919799/functions/getaddrinfo.html," + "POSIX specification} for more details.\n") +#define FUNC_NAME s_scm_getaddrinfo +{ + int err; + char *c_name, *c_service; + struct addrinfo c_hints, *c_result; + SCM result = SCM_EOL; + + if (scm_is_true (name)) + SCM_VALIDATE_STRING (SCM_ARG1, name); + + if (!SCM_UNBNDP (service) && scm_is_true (service)) + SCM_VALIDATE_STRING (SCM_ARG2, service); + + scm_dynwind_begin (0); + + if (scm_is_string (name)) + { + c_name = scm_to_locale_string (name); + scm_dynwind_free (c_name); + } + else + c_name = NULL; + + if (scm_is_string (service)) + { + c_service = scm_to_locale_string (service); + scm_dynwind_free (c_service); + } + else + c_service = NULL; + + memset (&c_hints, 0, sizeof (c_hints)); + if (!SCM_UNBNDP (hint_flags)) + { + c_hints.ai_flags = scm_to_int (hint_flags); + if (!SCM_UNBNDP (hint_family)) + { + c_hints.ai_family = scm_to_int (hint_family); + if (!SCM_UNBNDP (hint_socktype)) + { + c_hints.ai_socktype = scm_to_int (hint_socktype); + if (!SCM_UNBNDP (hint_family)) + c_hints.ai_family = scm_to_int (hint_family); + } + } + } -void + err = getaddrinfo (c_name, c_service, &c_hints, &c_result); + if (err == 0) + { + SCM *prev_addr; + struct addrinfo *a; + + for (prev_addr = &result, a = c_result; + a != NULL; + a = a->ai_next, prev_addr = SCM_CDRLOC (*prev_addr)) + *prev_addr = scm_list_1 (scm_from_addrinfo (a)); + + freeaddrinfo (c_result); + } + else + scm_throw (sym_getaddrinfo_error, scm_list_1 (scm_from_int (err))); + + scm_dynwind_end (); + + return result; +} +#undef FUNC_NAME + +/* Make sure the `EAI_*' flags can be stored as INUMs. */ +verify (SCM_I_INUM (SCM_I_MAKINUM (EAI_BADFLAGS)) == EAI_BADFLAGS); + +/* Error codes returned by `getaddrinfo'. */ +SCM_VARIABLE_INIT (sym_eai_badflags, "EAI_BADFLAGS", + SCM_I_MAKINUM (EAI_BADFLAGS)); +SCM_VARIABLE_INIT (sym_eai_noname, "EAI_NONAME", + SCM_I_MAKINUM (EAI_NONAME)); +SCM_VARIABLE_INIT (sym_eai_again, "EAI_AGAIN", + SCM_I_MAKINUM (EAI_AGAIN)); +SCM_VARIABLE_INIT (sym_eai_fail, "EAI_FAIL", + SCM_I_MAKINUM (EAI_FAIL)); +SCM_VARIABLE_INIT (sym_eai_family, "EAI_FAMILY", + SCM_I_MAKINUM (EAI_FAMILY)); +SCM_VARIABLE_INIT (sym_eai_socktype, "EAI_SOCKTYPE", + SCM_I_MAKINUM (EAI_SOCKTYPE)); +SCM_VARIABLE_INIT (sym_eai_service, "EAI_SERVICE", + SCM_I_MAKINUM (EAI_SERVICE)); +SCM_VARIABLE_INIT (sym_eai_memory, "EAI_MEMORY", + SCM_I_MAKINUM (EAI_MEMORY)); +SCM_VARIABLE_INIT (sym_eai_system, "EAI_SYSTEM", + SCM_I_MAKINUM (EAI_SYSTEM)); +SCM_VARIABLE_INIT (sym_eai_overflow, "EAI_OVERFLOW", + SCM_I_MAKINUM (EAI_OVERFLOW)); + +/* The following values are GNU extensions. */ +#ifdef EAI_NODATA +SCM_VARIABLE_INIT (sym_eai_nodata, "EAI_NODATA", + SCM_I_MAKINUM (EAI_NODATA)); +#endif +#ifdef EAI_ADDRFAMILY +SCM_VARIABLE_INIT (sym_eai_addrfamily, "EAI_ADDRFAMILY", + SCM_I_MAKINUM (EAI_ADDRFAMILY)); +#endif +#ifdef EAI_INPROGRESS +SCM_VARIABLE_INIT (sym_eai_inprogress, "EAI_INPROGRESS", + SCM_I_MAKINUM (EAI_INPROGRESS)); +#endif +#ifdef EAI_CANCELED +SCM_VARIABLE_INIT (sym_eai_canceled, "EAI_CANCELED", + SCM_I_MAKINUM (EAI_CANCELED)); +#endif +#ifdef EAI_NOTCANCELED +SCM_VARIABLE_INIT (sym_eai_notcanceled, "EAI_NOTCANCELED", + SCM_I_MAKINUM (EAI_NOTCANCELED)); +#endif +#ifdef EAI_ALLDONE +SCM_VARIABLE_INIT (sym_eai_alldone, "EAI_ALLDONE", + SCM_I_MAKINUM (EAI_ALLDONE)); +#endif +#ifdef EAI_INTR +SCM_VARIABLE_INIT (sym_eai_intr, "EAI_INTR", + SCM_I_MAKINUM (EAI_INTR)); +#endif +#ifdef EAI_IDN_ENCODE +SCM_VARIABLE_INIT (sym_eai_idn_encode, "EAI_IDN_ENCODE", + SCM_I_MAKINUM (EAI_IDN_ENCODE)); +#endif + +SCM_DEFINE (scm_gai_strerror, "gai-strerror", 1, 0, 0, + (SCM error), + "Return a string describing @var{error}, an integer error code " + "returned by @code{getaddrinfo}.") +#define FUNC_NAME s_scm_gai_strerror +{ + return scm_from_locale_string (gai_strerror (scm_to_int (error))); +} +#undef FUNC_NAME + +/* TODO: Add a getnameinfo(3) wrapper. */ + + +void scm_init_net_db () { scm_add_feature ("net-db"); |