fish-shell/env_universal_common.cpp
2013-10-19 22:10:26 +02:00

958 lines
20 KiB
C++

/**
\file env_universal_common.c
The utility library for universal variables. Used both by the
client library and by the daemon.
*/
#include "config.h"
#include <stdlib.h>
#include <stdio.h>
#include <wchar.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <pwd.h>
#include <errno.h>
#include <sys/stat.h>
#include <dirent.h>
#include <wctype.h>
#include <iconv.h>
#include <errno.h>
#include <locale.h>
#include <dirent.h>
#include <signal.h>
#include <sys/stat.h>
#include <map>
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
#include "fallback.h"
#include "util.h"
#include "common.h"
#include "wutil.h"
#include "env_universal_common.h"
/**
Non-wide version of the set command
*/
#define SET_MBS "SET"
/**
Non-wide version of the set_export command
*/
#define SET_EXPORT_MBS "SET_EXPORT"
/**
Non-wide version of the erase command
*/
#define ERASE_MBS "ERASE"
/**
Non-wide version of the barrier command
*/
#define BARRIER_MBS "BARRIER"
/**
Non-wide version of the barrier_reply command
*/
#define BARRIER_REPLY_MBS "BARRIER_REPLY"
/**
Error message
*/
#define PARSE_ERR L"Unable to parse universal variable message: '%ls'"
/**
ERROR string for internal buffered reader
*/
#define ENV_UNIVERSAL_ERROR 0x100
/**
EAGAIN string for internal buffered reader
*/
#define ENV_UNIVERSAL_AGAIN 0x101
/**
EOF string for internal buffered reader
*/
#define ENV_UNIVERSAL_EOF 0x102
/**
A variable entry. Stores the value of a variable and whether it
should be exported. Obviously, it needs to be allocated large
enough to fit the value string.
*/
typedef struct var_uni_entry
{
bool exportv; /**< Whether the variable should be exported */
wcstring val; /**< The value of the variable */
var_uni_entry():exportv(false), val() { }
}
var_uni_entry_t;
static void parse_message(wchar_t *msg,
connection_t *src);
/**
The table of all universal variables
*/
typedef std::map<wcstring, var_uni_entry_t> env_var_table_t;
env_var_table_t env_universal_var;
/**
Callback function, should be called on all events
*/
static void (*callback)(fish_message_type_t type,
const wchar_t *key,
const wchar_t *val);
/**
List of names for the UTF-8 character set.
*/
static const char *iconv_utf8_names[]=
{
"utf-8", "UTF-8",
"utf8", "UTF8",
0
}
;
/**
List of wide character names, undefined byte length.
*/
static const char *iconv_wide_names_unknown[]=
{
"wchar_t", "WCHAR_T",
"wchar", "WCHAR",
0
}
;
/**
List of wide character names, 4 bytes long.
*/
static const char *iconv_wide_names_4[]=
{
"wchar_t", "WCHAR_T",
"wchar", "WCHAR",
"ucs-4", "UCS-4",
"ucs4", "UCS4",
"utf-32", "UTF-32",
"utf32", "UTF32",
0
}
;
/**
List of wide character names, 2 bytes long.
*/
static const char *iconv_wide_names_2[]=
{
"wchar_t", "WCHAR_T",
"wchar", "WCHAR",
"ucs-2", "UCS-2",
"ucs2", "UCS2",
"utf-16", "UTF-16",
"utf16", "UTF16",
0
}
;
template<class T>
class sloppy {};
static size_t hack_iconv(iconv_t cd, const char * const* inbuf, size_t *inbytesleft, char **outbuf, size_t *outbytesleft)
{
/* FreeBSD has this prototype: size_t iconv (iconv_t, const char **...)
OS X and Linux this one: size_t iconv (iconv_t, char **...)
AFAIK there's no single type that can be passed as both char ** and const char **.
Therefore, we let C++ figure it out, by providing a struct with an implicit conversion to both char** and const char **.
*/
struct sloppy_char
{
const char * const * t;
operator char** () const
{
return (char **)t;
}
operator const char** () const
{
return (const char**)t;
}
} slop_inbuf = {inbuf};
return iconv(cd, slop_inbuf, inbytesleft, outbuf, outbytesleft);
}
/**
Convert utf-8 string to wide string
*/
static wchar_t *utf2wcs(const char *in)
{
iconv_t cd=(iconv_t) -1;
int i,j;
wchar_t *out;
/*
Try to convert to wchar_t. If that is not a valid character set,
try various names for ucs-4. We can't be sure that ucs-4 is
really the character set used by wchar_t, but it is the best
assumption we can make.
*/
const char **to_name=0;
switch (sizeof(wchar_t))
{
case 2:
to_name = iconv_wide_names_2;
break;
case 4:
to_name = iconv_wide_names_4;
break;
default:
to_name = iconv_wide_names_unknown;
break;
}
/*
The line protocol fish uses is always utf-8.
*/
const char **from_name = iconv_utf8_names;
size_t in_len = strlen(in);
size_t out_len = sizeof(wchar_t)*(in_len+2);
size_t nconv;
char *nout;
out = (wchar_t *)malloc(out_len);
nout = (char *)out;
if (!out)
return 0;
for (i=0; to_name[i]; i++)
{
for (j=0; from_name[j]; j++)
{
cd = iconv_open(to_name[i], from_name[j]);
if (cd != (iconv_t) -1)
{
goto start_conversion;
}
}
}
start_conversion:
if (cd == (iconv_t) -1)
{
/* Something went wrong. */
debug(0, L"Could not perform utf-8 conversion");
if (errno != EINVAL)
wperror(L"iconv_open");
/* Terminate the output string. */
free(out);
return 0;
}
/* FreeBSD has this prototype: size_t iconv (iconv_t, const char **...)
OS X and Linux this one: size_t iconv (iconv_t, char **...)
AFAIK there's no single type that can be passed as both char ** and const char **.
Hence this hack.
*/
nconv = hack_iconv(cd, &in, &in_len, &nout, &out_len);
if (nconv == (size_t) -1)
{
debug(0, L"Error while converting from utf string");
return 0;
}
*((wchar_t *) nout) = L'\0';
/*
Check for silly iconv behaviour inserting an bytemark in the output
string.
*/
if (*out == L'\xfeff' || *out == L'\xffef' || *out == L'\xefbbbf')
{
wchar_t *out_old = out;
out = wcsdup(out+1);
if (! out)
{
debug(0, L"FNORD!!!!");
free(out_old);
return 0;
}
free(out_old);
}
if (iconv_close(cd) != 0)
wperror(L"iconv_close");
return out;
}
/**
Convert wide string to utf-8
*/
static char *wcs2utf(const wchar_t *in)
{
iconv_t cd=(iconv_t) -1;
int i,j;
char *char_in = (char *)in;
char *out;
/*
Try to convert to wchar_t. If that is not a valid character set,
try various names for ucs-4. We can't be sure that ucs-4 is
really the character set used by wchar_t, but it is the best
assumption we can make.
*/
const char **from_name=0;
switch (sizeof(wchar_t))
{
case 2:
from_name = iconv_wide_names_2;
break;
case 4:
from_name = iconv_wide_names_4;
break;
default:
from_name = iconv_wide_names_unknown;
break;
}
const char **to_name = iconv_utf8_names;
size_t in_len = wcslen(in);
size_t out_len = sizeof(char)*((MAX_UTF8_BYTES*in_len)+1);
size_t nconv;
char *nout;
out = (char *)malloc(out_len);
nout = (char *)out;
in_len *= sizeof(wchar_t);
if (!out)
return 0;
for (i=0; to_name[i]; i++)
{
for (j=0; from_name[j]; j++)
{
cd = iconv_open(to_name[i], from_name[j]);
if (cd != (iconv_t) -1)
{
goto start_conversion;
}
}
}
start_conversion:
if (cd == (iconv_t) -1)
{
/* Something went wrong. */
debug(0, L"Could not perform utf-8 conversion");
if (errno != EINVAL)
wperror(L"iconv_open");
/* Terminate the output string. */
free(out);
return 0;
}
nconv = hack_iconv(cd, &char_in, &in_len, &nout, &out_len);
if (nconv == (size_t) -1)
{
debug(0, L"%d %d", in_len, out_len);
debug(0, L"Error while converting from to string");
/* Terminate the output string. */
free(out);
return 0;
}
*nout = '\0';
if (iconv_close(cd) != 0)
wperror(L"iconv_close");
return out;
}
void env_universal_common_init(void (*cb)(fish_message_type_t type, const wchar_t *key, const wchar_t *val))
{
callback = cb;
}
/**
Read one byte of date form the specified connection
*/
static int read_byte(connection_t *src)
{
if (src->buffer_consumed >= src->read_buffer.size())
{
char local[ENV_UNIVERSAL_BUFFER_SIZE];
ssize_t res = read(src->fd, local, sizeof local);
// debug(4, L"Read chunk '%.*s'", res, src->buffer );
if (res < 0)
{
if (errno == EAGAIN ||
errno == EINTR)
{
return ENV_UNIVERSAL_AGAIN;
}
return ENV_UNIVERSAL_ERROR;
}
else if (res == 0)
{
return ENV_UNIVERSAL_EOF;
}
else
{
src->read_buffer.clear();
src->read_buffer.insert(src->read_buffer.begin(), local, local + res);
src->buffer_consumed = 0;
}
}
return src->read_buffer.at(src->buffer_consumed++);
}
void read_message(connection_t *src)
{
while (1)
{
int ib = read_byte(src);
char b;
switch (ib)
{
case ENV_UNIVERSAL_AGAIN:
{
return;
}
case ENV_UNIVERSAL_ERROR:
{
debug(2, L"Read error on fd %d, set killme flag", src->fd);
if (debug_level > 2)
wperror(L"read");
src->killme = 1;
return;
}
case ENV_UNIVERSAL_EOF:
{
src->killme = 1;
debug(3, L"Fd %d has reached eof, set killme flag", src->fd);
if (! src->input.empty())
{
char c = 0;
src->input.push_back(c);
debug(1,
L"Universal variable connection closed while reading command. Partial command recieved: '%s'",
&src->input.at(0));
}
return;
}
}
b = (char)ib;
if (b == '\n')
{
wchar_t *msg;
b = 0;
src->input.push_back(b);
msg = utf2wcs(&src->input.at(0));
/*
Before calling parse_message, we must empty reset
everything, since the callback function could
potentially call read_message.
*/
src->input.clear();
if (msg)
{
parse_message(msg, src);
}
else
{
debug(0, _(L"Could not convert message '%s' to wide character string"), &src->input.at(0));
}
free(msg);
}
else
{
src->input.push_back(b);
}
}
}
/**
Remove variable with specified name
*/
void env_universal_common_remove(const wcstring &name)
{
env_universal_var.erase(name);
}
/**
Test if the message msg contains the command cmd
*/
static bool match(const wchar_t *msg, const wchar_t *cmd)
{
size_t len = wcslen(cmd);
if (wcsncasecmp(msg, cmd, len) != 0)
return false;
if (msg[len] && msg[len]!= L' ' && msg[len] != L'\t')
return false;
return true;
}
void env_universal_common_set(const wchar_t *key, const wchar_t *val, bool exportv)
{
CHECK(key,);
CHECK(val,);
var_uni_entry_t &entry = env_universal_var[key];
entry.exportv=exportv;
entry.val = val;
if (callback)
{
callback(exportv?SET_EXPORT:SET, key, val);
}
}
/**
Parse message msg
*/
static void parse_message(wchar_t *msg,
connection_t *src)
{
// debug( 3, L"parse_message( %ls );", msg );
if (msg[0] == L'#')
return;
if (match(msg, SET_STR) || match(msg, SET_EXPORT_STR))
{
wchar_t *name, *tmp;
bool exportv = match(msg, SET_EXPORT_STR);
name = msg+(exportv?wcslen(SET_EXPORT_STR):wcslen(SET_STR));
while (wcschr(L"\t ", *name))
name++;
tmp = wcschr(name, L':');
if (tmp)
{
wchar_t *val;
const wcstring key(name, tmp - name);
val = tmp+1;
val = unescape(val, 0);
if (val != NULL)
env_universal_common_set(key.c_str(), val, exportv);
free(val);
}
else
{
debug(1, PARSE_ERR, msg);
}
}
else if (match(msg, ERASE_STR))
{
wchar_t *name, *tmp;
name = msg+wcslen(ERASE_STR);
while (wcschr(L"\t ", *name))
name++;
tmp = name;
while (iswalnum(*tmp) || *tmp == L'_')
tmp++;
*tmp = 0;
if (!wcslen(name))
{
debug(1, PARSE_ERR, msg);
}
env_universal_common_remove(name);
if (callback)
{
callback(ERASE, name, 0);
}
}
else if (match(msg, BARRIER_STR))
{
message_t *msg = create_message(BARRIER_REPLY, 0, 0);
msg->count = 1;
src->unsent.push(msg);
try_send_all(src);
}
else if (match(msg, BARRIER_REPLY_STR))
{
if (callback)
{
callback(BARRIER_REPLY, 0, 0);
}
}
else
{
debug(1, PARSE_ERR, msg);
}
}
/**
Attempt to send the specified message to the specified file descriptor
\return 1 on sucess, 0 if the message could not be sent without blocking and -1 on error
*/
static int try_send(message_t *msg,
int fd)
{
debug(3,
L"before write of %d chars to fd %d", msg->body.size(), fd);
ssize_t res = write(fd, msg->body.c_str(), msg->body.size());
if (res != -1)
{
debug(4, L"Wrote message '%s'", msg->body.c_str());
}
else
{
debug(4, L"Failed to write message '%s'", msg->body.c_str());
}
if (res == -1)
{
switch (errno)
{
case EAGAIN:
return 0;
default:
debug(2,
L"Error while sending universal variable message to fd %d. Closing connection",
fd);
if (debug_level > 2)
wperror(L"write");
return -1;
}
}
msg->count--;
if (!msg->count)
{
delete msg;
}
return 1;
}
void try_send_all(connection_t *c)
{
/* debug( 3,
L"Send all updates to connection on fd %d",
c->fd );*/
while (!c->unsent.empty())
{
switch (try_send(c->unsent.front(), c->fd))
{
case 1:
c->unsent.pop();
break;
case 0:
debug(4,
L"Socket full, send rest later");
return;
case -1:
c->killme = 1;
return;
}
}
}
/* The universal variable format has some funny escaping requirements; here we try to be safe */
static bool is_universal_safe_to_encode_directly(wchar_t c)
{
if (c < 32 || c > 128)
return false;
return iswalnum(c) || wcschr(L"/", c);
}
/**
Escape specified string
*/
static wcstring full_escape(const wchar_t *in)
{
wcstring out;
for (; *in; in++)
{
wchar_t c = *in;
if (is_universal_safe_to_encode_directly(c))
{
out.push_back(c);
}
else if (c < 256)
{
append_format(out, L"\\x%.2x", c);
}
else if (c < 65536)
{
append_format(out, L"\\u%.4x", c);
}
else
{
append_format(out, L"\\U%.8x", c);
}
}
return out;
}
/* Sets the body of a message to the null-terminated list of null terminated const char *. */
void set_body(message_t *msg, ...)
{
/* Start by counting the length of all the strings */
size_t body_len = 0;
const char *arg;
va_list arg_list;
va_start(arg_list, msg);
while ((arg = va_arg(arg_list, const char *)) != NULL)
body_len += strlen(arg);
va_end(arg_list);
/* Reserve that length in the string */
msg->body.reserve(body_len + 1); //+1 for trailing NULL? Do I need that?
/* Set the string contents */
va_start(arg_list, msg);
while ((arg = va_arg(arg_list, const char *)) != NULL)
msg->body.append(arg);
va_end(arg_list);
}
/* Returns an instance of message_t allocated via new */
message_t *create_message(fish_message_type_t type,
const wchar_t *key_in,
const wchar_t *val_in)
{
char *key = NULL;
// debug( 4, L"Crete message of type %d", type );
if (key_in)
{
if (wcsvarname(key_in))
{
debug(0, L"Illegal variable name: '%ls'", key_in);
return NULL;
}
key = wcs2utf(key_in);
if (!key)
{
debug(0,
L"Could not convert %ls to narrow character string",
key_in);
return NULL;
}
}
message_t *msg = new message_t;
msg->count = 0;
switch (type)
{
case SET:
case SET_EXPORT:
{
if (!val_in)
{
val_in=L"";
}
wcstring esc = full_escape(val_in);
char *val = wcs2utf(esc.c_str());
set_body(msg, (type==SET?SET_MBS:SET_EXPORT_MBS), " ", key, ":", val, "\n", NULL);
free(val);
break;
}
case ERASE:
{
set_body(msg, ERASE_MBS, " ", key, "\n", NULL);
break;
}
case BARRIER:
{
set_body(msg, BARRIER_MBS, "\n", NULL);
break;
}
case BARRIER_REPLY:
{
set_body(msg, BARRIER_REPLY_MBS, "\n", NULL);
break;
}
default:
{
debug(0, L"create_message: Unknown message type");
}
}
free(key);
// debug( 4, L"Message body is '%s'", msg->body );
return msg;
}
/**
Put exported or unexported variables in a string list
*/
void env_universal_common_get_names(wcstring_list_t &lst,
bool show_exported,
bool show_unexported)
{
env_var_table_t::const_iterator iter;
for (iter = env_universal_var.begin(); iter != env_universal_var.end(); ++iter)
{
const wcstring &key = iter->first;
const var_uni_entry_t &e = iter->second;
if ((e.exportv && show_exported) || (! e.exportv && show_unexported))
{
lst.push_back(key);
}
}
}
const wchar_t *env_universal_common_get(const wcstring &name)
{
env_var_table_t::const_iterator result = env_universal_var.find(name);
if (result != env_universal_var.end())
{
const var_uni_entry_t &e = result->second;
return const_cast<wchar_t*>(e.val.c_str());
}
return NULL;
}
bool env_universal_common_get_export(const wcstring &name)
{
env_var_table_t::const_iterator result = env_universal_var.find(name);
if (result != env_universal_var.end())
{
const var_uni_entry_t &e = result->second;
return e.exportv;
}
return false;
}
void enqueue_all(connection_t *c)
{
env_var_table_t::const_iterator iter;
for (iter = env_universal_var.begin(); iter != env_universal_var.end(); ++iter)
{
const wcstring &key = iter->first;
const var_uni_entry_t &entry = iter->second;
message_t *msg = create_message(entry.exportv ? SET_EXPORT : SET, key.c_str(), entry.val.c_str());
msg->count=1;
c->unsent.push(msg);
}
try_send_all(c);
}
connection_t::connection_t(int input_fd) :
fd(input_fd),
killme(false),
buffer_consumed(0)
{
}
void connection_destroy(connection_t *c)
{
/*
A connection need not always be open - we only try to close it
if it is open.
*/
if (c->fd >= 0)
{
if (close(c->fd))
{
wperror(L"close");
}
}
}