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sortix--sortix/sh/sh.c
Jonas 'Sortie' Termansen 8d7d364037 Switch sh(1) to termios.
sh(1) now restores reasonable terminal attributes. This is not really its
problem, but as long as common Sortix programs don't always restore the
terminal attributes on exit, this will work around the issue in practice.
2016-11-22 21:36:43 +01:00

2251 lines
50 KiB
C

/*
* Copyright (c) 2011, 2012, 2013, 2014, 2015 Jonas 'Sortie' Termansen.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* sh.c
* Command language interpreter.
*/
#include <sys/stat.h>
#include <sys/wait.h>
#include <assert.h>
#include <ctype.h>
#include <dirent.h>
#include <errno.h>
#include <error.h>
#include <fcntl.h>
#include <inttypes.h>
#include <ioleast.h>
#include <libgen.h>
#include <limits.h>
#include <locale.h>
#include <sched.h>
#include <signal.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <termios.h>
#include <unistd.h>
#include <wchar.h>
#include <wctype.h>
// Sortix libc doesn't have its own proper <limits.h> at this time.
#if defined(__sortix__)
#include <sortix/limits.h>
#endif
#include "editline.h"
#include "showline.h"
#include "util.h"
const char* builtin_commands[] =
{
"cd",
"exit",
"unset",
"clearenv",
(const char*) NULL,
};
int status = 0;
bool foreground_shell;
static bool is_proper_absolute_path(const char* path)
{
if ( path[0] == '\0' )
return false;
if ( path[0] != '/' )
return false;
while ( path[0] )
{
if ( path[0] == '/' )
path++;
else if ( path[0] == '.' &&
(path[1] == '\0' || path[1] == '/') )
return false;
else if ( path[0] == '.' &&
path[1] == '.' &&
(path[2] == '\0' || path[2] == '/') )
return false;
else
{
while ( *path && *path != '/' )
path++;
}
}
return true;
}
void update_env(void)
{
char str[3 * sizeof(size_t)];
struct winsize ws;
if ( tcgetwinsize(0, &ws) == 0 )
{
snprintf(str, sizeof(str), "%zu", ws.ws_col);
setenv("COLUMNS", str, 1);
snprintf(str, sizeof(str), "%zu", ws.ws_row);
setenv("LINES", str, 1);
}
}
bool matches_simple_pattern(const char* string, const char* pattern)
{
size_t wildcard_index = strcspn(pattern, "*");
if ( !pattern[wildcard_index] )
return strcmp(string, pattern) == 0;
if ( pattern[0] == '*' && string[0] == '.' )
return false;
size_t string_length = strlen(string);
size_t pattern_length = strlen(pattern);
size_t pattern_last = pattern_length - (wildcard_index + 1);
return strncmp(string, pattern, wildcard_index) == 0 &&
strcmp(string + string_length - pattern_last,
pattern + wildcard_index + 1) == 0;
}
void array_shrink_free(void*** array_ptr,
size_t* used_ptr,
size_t* length_ptr,
size_t new_used)
{
void** array;
memcpy(&array, array_ptr, sizeof(array)); // Strict aliasing.
for ( size_t i = new_used; i < *used_ptr; i++ )
{
void* value;
memcpy(&value, array + i, sizeof(value)); // Strict aliasing.
free(value);
}
*used_ptr = new_used;
(void) length_ptr;
}
char* token_finalize(const char* token)
{
struct stringbuf buf;
stringbuf_begin(&buf);
bool escape = false;
bool single_quote = false;
bool double_quote = false;
for ( size_t i = 0; token[i]; i++ )
{
if ( !escape && !single_quote && token[i] == '\\' )
{
escape = true;
}
else if ( !escape && !double_quote && token[i] == '\'' )
{
single_quote = !single_quote;
}
else if ( !escape && !single_quote && token[i] == '"' )
{
double_quote = !double_quote;
}
else if ( escape && token[i] == '\n' )
{
escape = false;
}
else
{
stringbuf_append_c(&buf, token[i]);
escape = false;
}
}
return stringbuf_finish(&buf);
}
bool is_identifier_char(char c)
{
return ('a' <= c && c <= 'z') ||
('A' <= c && c <= 'Z') ||
('0' <= c && c <= '9') ||
c == '_';
}
char* token_expand_variables(const char* token)
{
struct stringbuf buf;
stringbuf_begin(&buf);
bool escape = false;
bool single_quote = false;
bool double_quote = false;
for ( size_t i = 0; token[i]; i++ )
{
if ( !escape && !single_quote && token[i] == '\\' )
{
stringbuf_append_c(&buf, '\\');
escape = true;
}
else if ( !escape && !double_quote && token[i] == '\'' )
{
stringbuf_append_c(&buf, '\'');
single_quote = !single_quote;
}
else if ( !escape && !single_quote && token[i] == '"' )
{
stringbuf_append_c(&buf, '"');
double_quote = !double_quote;
}
else if ( !escape && !single_quote && token[i] == '$' && token[i + 1] )
{
i++;
const char* value;
if ( token[i] == '{' )
{
i++;
size_t length = 0;
while ( token[i + length] && token[i + length] != '}' )
length++;
char* variable = strndup(token + i, length);
if ( !variable )
return free(buf.string), (char*) NULL;
value = getenv(variable);
free(variable);
i += length;
if ( token[i] == '}' )
i++;
i--;
}
else if ( is_identifier_char(token[i]) )
{
size_t length = 1;
while ( is_identifier_char(token[i + length]) )
length++;
char* variable = strndup(token + i, length);
if ( !variable )
return free(buf.string), (char*) NULL;
value = getenv(variable);
free(variable);
i += length - 1;
}
else
{
char variable[2] = { token[i], '\0' };
value = getenv(variable);
}
for ( size_t n = 0; value && value[n]; n++ )
{
if ( double_quote && might_need_shell_quote(value[i]) )
stringbuf_append_c(&buf, '\\');
stringbuf_append_c(&buf, value[n]);
}
}
else
{
stringbuf_append_c(&buf, token[i]);
escape = false;
}
}
return stringbuf_finish(&buf);
}
bool token_split(void*** out,
size_t* out_used,
size_t* out_length,
const char* token)
{
size_t old_used = *out_used;
size_t index = 0;
while ( true )
{
while ( token[index] && isspace((unsigned char) token[index]) )
index++;
if ( !token[index] )
break;
struct stringbuf buf;
stringbuf_begin(&buf);
bool escape = false;
bool single_quote = false;
bool double_quote = false;
for ( ; token[index]; index++ )
{
if ( !escape && !single_quote && token[index] == '\\' )
{
stringbuf_append_c(&buf, '\\');
escape = true;
}
else if ( !escape && !double_quote && token[index] == '\'' )
{
stringbuf_append_c(&buf, '\'');
single_quote = !single_quote;
}
else if ( !escape && !single_quote && token[index] == '"' )
{
stringbuf_append_c(&buf, '"');
double_quote = !double_quote;
}
else if ( !(escape || single_quote || double_quote) &&
isspace((unsigned char) token[index]) )
{
break;
}
else if ( escape && token[index] == '\n' )
{
escape = false;
}
else
{
stringbuf_append_c(&buf, token[index]);
escape = false;
}
}
char* value = stringbuf_finish(&buf);
if ( !value )
{
array_shrink_free(out, out_used, out_length, old_used);
return false;
}
if ( !array_add(out, out_used, out_length, value) )
{
array_shrink_free(out, out_used, out_length, old_used);
return false;
}
}
return true;
}
bool token_expand_variables_split(void*** out,
size_t* out_used,
size_t* out_length,
const char* token)
{
char* expanded = token_expand_variables(token);
if ( !expanded )
return false;
bool result = token_split(out, out_used, out_length, expanded);
free(expanded);
return result;
}
static int strcoll_indirect(const void* a_ptr, const void* b_ptr)
{
const char* a = *(const char* const*) a_ptr;
const char* b = *(const char* const*) b_ptr;
return strcoll(a, b);
}
bool token_expand_wildcards(void*** out,
size_t* out_used,
size_t* out_length,
const char* token)
{
size_t old_used = *out_used;
size_t index = 0;
size_t num_escaped_wildcards = 0; // We don't properly support them yet.
struct stringbuf buf;
stringbuf_begin(&buf);
bool escape = false;
bool single_quote = false;
bool double_quote = false;
for ( ; token[index]; index++ )
{
if ( !escape && !single_quote && token[index] == '\\' )
{
escape = true;
}
else if ( !escape && !double_quote && token[index] == '\'' )
{
single_quote = !single_quote;
}
else if ( !escape && !single_quote && token[index] == '"' )
{
double_quote = !double_quote;
}
else if ( !(escape || single_quote || double_quote) &&
token[index] == '*' )
{
break;
}
else
{
if ( token[index] == '*' )
num_escaped_wildcards++;
stringbuf_append_c(&buf, token[index]);
escape = false;
}
}
if ( token[index] != '*' || num_escaped_wildcards )
{
char* value;
free(stringbuf_finish(&buf));
just_return_input:
value = strdup(token);
if ( !value )
return false;
if ( !array_add(out, out_used, out_length, value) )
return free(value), false;
return true;
}
char* before = stringbuf_finish(&buf);
if ( !before )
return false;
stringbuf_begin(&buf);
index++;
for ( ; token[index]; index++ )
{
if ( !escape && !single_quote && token[index] == '\\' )
{
escape = true;
}
else if ( !escape && !double_quote && token[index] == '\'' )
{
single_quote = !single_quote;
}
else if ( !escape && !single_quote && token[index] == '"' )
{
double_quote = !double_quote;
}
else if ( !(escape || single_quote || double_quote) &&
token[index] == '*' )
{
break;
}
else
{
if ( token[index] == '*' )
num_escaped_wildcards++;
stringbuf_append_c(&buf, token[index]);
escape = false;
}
}
if ( token[index] == '*' )
{
// TODO: We don't support double use of wildcards yet.
free(stringbuf_finish(&buf));
free(before);
goto just_return_input;
}
char* after = stringbuf_finish(&buf);
if ( !after )
return free(before), false;
char* pattern;
if ( asprintf(&pattern, "%s*%s", before, after) < 0 )
return free(after), free(before), false;
free(after);
free(before);
size_t wildcard_pos = strcspn(pattern, "*");
bool found_slash = false;
size_t last_slash = 0;
for ( size_t n = 0; n < wildcard_pos; n++ )
if ( pattern[n] == '/' )
last_slash = n, found_slash = true;
size_t match_from = found_slash ? last_slash + 1 : 0;
size_t pattern_prefix = 0;
DIR* dir = NULL;
if ( !found_slash )
{
if ( !(dir = opendir(".")) )
{
free(pattern);
goto just_return_input;
}
}
else
{
char* dirpath = strdup(pattern);
if ( !dirpath )
{
free(pattern);
goto just_return_input;
}
dirpath[last_slash] = '\0';
pattern_prefix = last_slash + 1;
dir = opendir(dirpath);
free(dirpath);
if ( !dir )
{
free(pattern);
goto just_return_input;
}
}
size_t num_inserted = 0;
struct dirent* entry;
while ( (entry = readdir(dir)) )
{
if ( !matches_simple_pattern(entry->d_name, pattern + match_from) )
continue;
stringbuf_begin(&buf);
for ( size_t i = 0; i < pattern_prefix; i++ )
{
if ( pattern[i] == '\n' )
{
stringbuf_append_c(&buf, '\'');
stringbuf_append_c(&buf, '\n');
stringbuf_append_c(&buf, '\'');
}
else
{
if ( might_need_shell_quote(pattern[i]) )
stringbuf_append_c(&buf, '\\');
stringbuf_append_c(&buf, pattern[i]);
}
}
for ( size_t i = 0; entry->d_name[i]; i++ )
{
if ( entry->d_name[i] == '\n' )
{
stringbuf_append_c(&buf, '\'');
stringbuf_append_c(&buf, '\n');
stringbuf_append_c(&buf, '\'');
}
else
{
if ( might_need_shell_quote(entry->d_name[i]) )
stringbuf_append_c(&buf, '\\');
stringbuf_append_c(&buf, entry->d_name[i]);
}
}
char* name = stringbuf_finish(&buf);
if ( !name )
{
free(pattern);
closedir(dir);
array_shrink_free(out, out_used, out_length, old_used);
return false;
}
if ( !array_add(out, out_used, out_length, name) )
{
free(name);
free(pattern);
closedir(dir);
array_shrink_free(out, out_used, out_length, old_used);
return false;
}
num_inserted++;
}
closedir(dir);
free(pattern);
if ( num_inserted == 0 )
goto just_return_input;
char** out_tokens;
memcpy(&out_tokens, out, sizeof(out_tokens));
char** sort_from = out_tokens + old_used;
size_t sort_count = *out_used - old_used;
qsort(sort_from, sort_count, sizeof(char*), strcoll_indirect);
return true;
}
enum sh_tokenize_result
{
SH_TOKENIZE_RESULT_OK,
SH_TOKENIZE_RESULT_PARTIAL,
SH_TOKENIZE_RESULT_INVALID,
SH_TOKENIZE_RESULT_ERROR,
};
bool can_continue_operator(const char* op, char c)
{
if ( !op )
return false;
if ( op[0] == '<' && op[1] == '<' && op[2] == '\0' )
return c == '-';
if ( op[0] == '|' && op[1] == '\0' )
return c == '|';
if ( op[0] == '&' && op[1] == '\0' )
return c == '&';
if ( op[0] == ';' && op[1] == '\0' )
return c == ';';
if ( op[0] == '<' && op[1] == '\0' )
return c == '<' || c == '&' || c == '>';
if ( op[0] == '>' && op[1] == '\0' )
return c == '>' || c == '&' || c == '|';
if ( op[0] == '\0' )
return c == '|' || c == '&' || c == ';' || c == '>' || c == '<' ||
c == '(' || c == ')';
return false;
}
enum sh_tokenize_result sh_tokenize(const char* command,
char*** tokens_ptr,
size_t* tokens_used_ptr,
size_t* tokens_length_ptr)
{
enum sh_tokenize_result result = SH_TOKENIZE_RESULT_OK;
char** tokens = NULL;
size_t tokens_used = 0;
size_t tokens_length = 0;
size_t command_index = 0;
while ( true )
{
if ( command[command_index] == '\0' )
break;
if ( isspace((unsigned char) command[command_index]) )
{
command_index++;
continue;
}
if ( command[command_index] == '#' )
{
while ( command[command_index] != '\0' &&
command[command_index] != '\n' )
command_index++;
continue;
}
struct stringbuf buf;
stringbuf_begin(&buf);
bool escaped = false;
bool single_quote = false;
bool double_quote = false;
bool stop = false;
bool making_operator = false;
while ( true )
{
if ( command[command_index] == '\0' )
{
if ( escaped || single_quote || double_quote )
result = SH_TOKENIZE_RESULT_PARTIAL;
stop = true;
break;
}
else if ( making_operator )
{
if ( can_continue_operator(buf.string, command[command_index]) )
{
stringbuf_append_c(&buf, command[command_index]);
command_index++;
}
else
{
break;
}
}
else if ( buf.string && buf.length == 0 &&
can_continue_operator("", command[command_index]) )
{
stringbuf_append_c(&buf, command[command_index]);
making_operator = true;
command_index++;
}
else if ( !escaped && !single_quote && command[command_index] == '\\' )
{
stringbuf_append_c(&buf, '\\');
escaped = true;
command_index++;
}
else if ( !escaped && !double_quote && command[command_index] == '\'' )
{
stringbuf_append_c(&buf, '\'');
single_quote = !single_quote;
command_index++;
}
else if ( !escaped && !single_quote && command[command_index] == '"' )
{
stringbuf_append_c(&buf, '"');
double_quote = !double_quote;
command_index++;
}
else if ( !(escaped || single_quote || double_quote) &&
(isspace((unsigned char) command[command_index]) ||
can_continue_operator("", command[command_index])) )
{
break;
}
else if ( escaped && command[command_index] == '\n' )
{
if ( buf.string && buf.length && buf.string[buf.length - 1] == '\\' )
buf.string[--buf.length] = '\0';
command_index++;
escaped = false;
}
else
{
stringbuf_append_c(&buf, command[command_index]);
command_index++;
escaped = false;
}
}
char* token = stringbuf_finish(&buf);
if ( !token )
{
result = SH_TOKENIZE_RESULT_ERROR;
break;
}
if ( !array_add((void***) &tokens,
&tokens_used,
&tokens_length,
token) )
{
free(token);
result = SH_TOKENIZE_RESULT_ERROR;
break;
}
if ( stop )
break;
}
*tokens_ptr = tokens;
*tokens_used_ptr = tokens_used;
*tokens_length_ptr = tokens_length;
return result;
}
bool is_shell_input_ready(const char* input)
{
char** tokens = NULL;
size_t tokens_used = 0;
size_t tokens_length = 0;
enum sh_tokenize_result tokenize_result =
sh_tokenize(input, &tokens, &tokens_used, &tokens_length);
bool result = tokenize_result == SH_TOKENIZE_RESULT_OK;
for ( size_t i = 0; i < tokens_used; i++ )
free(tokens[i]);
free(tokens);
return result;
}
int lexical_chdir(char* path)
{
assert(path[0] == '/');
int fd = open("/", O_RDONLY | O_DIRECTORY);
if ( fd < 0 )
return -1;
size_t input_index = 1;
size_t output_index = 1;
while ( path[input_index] )
{
if ( path[input_index] == '/' )
{
if ( output_index && path[output_index-1] != '/' )
path[output_index++] = path[input_index];
input_index++;
continue;
}
char* elem = path + input_index;
size_t elem_length = strcspn(elem, "/");
char lc = elem[elem_length];
elem[elem_length] = '\0';
if ( !strcmp(elem, ".") )
{
elem[elem_length] = lc;
input_index += elem_length;
continue;
}
if ( !strcmp(elem, "..") )
{
elem[elem_length] = lc;
input_index += elem_length;
if ( 2 <= output_index && path[output_index-1] == '/' )
output_index--;
while ( 2 <= output_index && path[output_index-1] != '/' )
output_index--;
if ( 2 <= output_index && path[output_index-1] == '/' )
output_index--;
lc = path[output_index];
path[output_index] = '\0';
int new_fd = open(path, O_RDONLY | O_DIRECTORY);
close(fd);
if ( new_fd < 0 )
return -1;
fd = new_fd;
path[output_index] = lc;
continue;
}
if ( 0 <= fd )
{
int new_fd = openat(fd, elem, O_RDONLY | O_DIRECTORY);
if ( new_fd < 0 )
close(fd);
fd = new_fd;
}
for ( size_t i = 0; i < elem_length; i++ )
path[output_index++] = path[input_index++];
elem[elem_length] = lc;
}
path[output_index] = '\0';
if ( 2 <= output_index && path[output_index-1] == '/' )
path[--output_index] = '\0';
int fchdir_ret = fchdir(fd);
close(fd);
if ( fchdir_ret < 0 )
return -1;
unsetenv("PWD");
setenv("PWD", path, 1);
return 0;
}
int perform_chdir(const char* path)
{
if ( !path[0] )
return errno = ENOENT, -1;
char* lexical_path = NULL;
if ( path[0] == '/' )
lexical_path = strdup(path);
else
{
char* current_pwd = get_current_dir_name();
if ( current_pwd )
{
assert(current_pwd[0] == '/');
asprintf(&lexical_path, "%s/%s", current_pwd, path);
free(current_pwd);
}
else if ( getenv("PWD") )
{
asprintf(&lexical_path, "/%s/%s", getenv("PWD"), path);
}
}
if ( lexical_path )
{
int ret = lexical_chdir(lexical_path);
free(lexical_path);
if ( ret == 0 )
return 0;
}
return chdir(path);
}
bool is_variable_assignment_token(const char* token)
{
size_t i = 0;
while ( is_identifier_char(token[i]) )
i++;
return i != 0 && token[i] == '=';
}
struct execute_result
{
pid_t pid;
int internal_status;
bool failure;
bool critical;
bool internal;
bool exited;
};
struct execute_result execute(char** tokens,
size_t tokens_count,
bool interactive,
int pipein,
int pipeout,
pid_t pgid)
{
char** varsv;
size_t varsc;
size_t varsv_allocated;
char** expandv;
size_t expandc;
size_t expandv_allocated;
char** argv;
size_t argc;
size_t argv_allocated;
bool internal;
bool failure = false;
bool critical = false;
bool do_exit = false;
bool set_pipein = false;
bool set_pipeout = false;
bool had_not_varassign = false;
pid_t childpid;
update_env();
char statusstr[sizeof(int) * 3];
snprintf(statusstr, sizeof(statusstr), "%i", status);
setenv("?", statusstr, 1);
varsv = NULL;
varsc = 0;
varsv_allocated = 0;
expandv = NULL;
expandc = 0;
expandv_allocated = 0;
for ( size_t i = 0; !failure && i < tokens_count; i++ )
{
if ( !had_not_varassign && is_variable_assignment_token(tokens[i]))
{
char* value = token_expand_variables(tokens[i]);
if ( !value )
{
error(0, errno, "variable expansion");
failure = true;
critical = true;
break;
}
if ( !array_add((void***) &varsv,
&varsc,
&varsv_allocated,
value) )
{
free(value);
error(0, errno, "variable expansion");
failure = true;
critical = true;
break;
}
}
else
{
had_not_varassign = true;
if ( !token_expand_variables_split((void***) &expandv,
&expandc,
&expandv_allocated,
tokens[i]) )
{
error(0, errno, "variable expansion");
failure = true;
critical = true;
break;
}
}
}
argv = NULL;
argc = 0;
argv_allocated = 0;
for ( size_t i = 0; !failure && i < expandc; i++ )
{
if ( !strcmp(expandv[i], "<") ||
!strcmp(expandv[i], ">") ||
/*!strcmp(expandv[i], "<<") ||*/
!strcmp(expandv[i], ">>") )
{
const char* type = expandv[i++];
if ( i == expandc )
{
error(0, errno, "%s: expected argument", type);
failure = true;
critical = true;
break;
}
char** targets = NULL;
size_t targets_used = 0;
size_t targets_length = 0;
if ( !token_expand_wildcards((void***) &targets,
&targets_used,
&targets_length,
expandv[i]) )
{
error(0, errno, "wildcard expansion");
failure = true;
critical = true;
break;
}
if ( targets_used != 1 )
{
error(0, 0, "%s: ambiguous redirect: %s", type, expandv[i]);
for ( size_t i = 0; i < targets_used; i++ )
free(targets[i]);
free(targets);
failure = true;
break;
}
char* target = token_finalize(targets[0]);
free(targets[0]);
free(targets);
if ( !target )
{
error(0, errno, "token finalization");
failure = true;
break;
}
int fd = -1;
if ( !strcmp(type, "<") )
fd = open(target, O_RDONLY | O_CLOEXEC);
else if ( !strcmp(type, ">") )
fd = open(target, O_WRONLY | O_CREAT | O_TRUNC | O_CLOEXEC, 0666);
else if ( !strcmp(type, ">>") )
fd = open(target, O_WRONLY | O_CREAT | O_APPEND | O_CLOEXEC, 0666);
if ( fd < 0 )
{
error(0, errno, "%s", target);
free(target);
failure = true;
break;
}
if ( !strcmp(type, "<") )
{
pipein = fd;
set_pipein = true;
}
else if ( !strcmp(type, ">") || !strcmp(type, ">>") )
{
pipeout = fd;
set_pipeout = true;
}
free(target);
}
else
{
if ( !token_expand_wildcards((void***) &argv,
&argc,
&argv_allocated,
expandv[i]) )
{
error(0, errno, "wildcard expansion");
failure = true;
critical = true;
break;
}
}
}
for ( size_t i = 0; i < expandc; i++ )
free(expandv[i]);
free(expandv);
if ( !array_add((void***) &argv, &argc, &argv_allocated, (char*) NULL) )
{
failure = true;
critical = true;
}
else
{
argc--; // Don't count the NULL.
}
for ( size_t i = 0; i < varsc; i++ )
{
char* var = token_finalize(varsv[i]);
if ( !var )
{
error(0, errno, "token finalization");
failure = true;
break;
}
free(varsv[i]);
varsv[i] = var;
}
for ( size_t i = 0; i < argc; i++ )
{
char* arg = token_finalize(argv[i]);
if ( !arg )
{
error(0, errno, "token finalization");
failure = true;
break;
}
free(argv[i]);
argv[i] = arg;
}
// TODO: Builtins should be run in a child process if & or |.
int internal_status = status;
if ( failure )
{
internal = true;
internal_status = 1;
}
else if ( argc == 0 )
{
internal = true;
for ( size_t i = 0; i < varsc; i++ )
{
char* key = varsv[i];
char* eq = strchr(key, '=');
if ( !eq )
continue;
*eq = '\0';
char* value = eq + 1;
int ret = setenv(key, value, 1);
*eq = '=';
if ( ret < 0 )
{
error(0, errno, "setenv");
internal_status = 1;
}
}
}
else if ( strcmp(argv[0], "cd") == 0 )
{
internal = true;
const char* newdir = argv[1];
if ( !newdir )
newdir = getenv_safe_def("HOME", "/");
internal_status = 0;
if ( perform_chdir(newdir) < 0 )
{
error(0, errno, "cd: %s", newdir);
internal_status = 1;
}
}
else if ( strcmp(argv[0], "exit") == 0 )
{
internal = true;
int exitcode = argv[1] ? atoi(argv[1]) : 0;
exitcode = (unsigned char) exitcode;
do_exit = true;
internal_status = exitcode;
}
else if ( strcmp(argv[0], "export") == 0 )
{
internal = true;
internal_status = 0;
if ( argv[1] )
{
size_t eqpos = strcspn(argv[1], "=");
if ( argv[1][eqpos] == '=' )
{
char* name = strndup(argv[1], eqpos);
if ( name )
{
if ( setenv(name, argv[1] + eqpos + 1, 1) < 0 )
{
error(0, errno, "export: setenv");
internal_status = 1;
}
}
else
{
error(0, errno, "export: malloc");
internal_status = 1;
}
}
}
else
{
for ( size_t i = 0; environ[i]; i++ )
{
const char* envvar = environ[i];
printf("export ");
while ( *envvar && *envvar != '=' )
putchar((unsigned char) *envvar++);
if ( *envvar == '=' )
putchar((unsigned char) *envvar++);
putchar('\'');
while ( *envvar )
{
if ( *envvar == '\'' )
{
putchar('\'');
putchar('\\');
putchar((unsigned char) *envvar++);
putchar('\'');
}
else
{
putchar((unsigned char) *envvar++);
}
}
putchar('\'');
putchar('\n');
}
}
}
else if ( strcmp(argv[0], "unset") == 0 )
{
internal = true;
unsetenv(argv[1] ? argv[1] : "");
internal_status = 0;
}
else if ( strcmp(argv[0], "clearenv") == 0 )
{
internal = true;
clearenv();
internal_status = 0;
}
else
{
internal = false;
}
if ( (childpid = internal ? getpid() : fork()) < 0 )
{
error(0, errno, "fork");
internal_status = 1;
failure = true;
internal = true;
childpid = getpid();
}
if ( childpid )
{
if ( set_pipein )
close(pipein);
if ( set_pipeout )
close(pipeout);
for ( size_t i = 0; i < varsc; i++ )
free(varsv[i]);
free(varsv);
for ( size_t i = 0; i < argc; i++ )
free(argv[i]);
free(argv);
if ( internal )
{
struct execute_result result;
memset(&result, 0, sizeof(result));
result.internal_status = internal_status;
result.failure = failure;
result.critical = critical;
result.internal = true;
result.exited = do_exit;
return result;
}
setpgid(childpid, pgid != -1 ? pgid : childpid);
// TODO: This is an inefficient manner to avoid a race condition where
// a pipeline foo | bar is running in its own process group and
// foo is the process group leader that sets itself as the
// foreground process group, but bar dies prior to foo's tcsetpgrp
// call, because then the shell would run tcsetpgrp to take back
// control, and only then would foo do its tcsetpgrp call.
while ( foreground_shell && pgid == -1 && tcgetpgrp(0) != childpid )
sched_yield();
struct execute_result result;
memset(&result, 0, sizeof(result));
result.pid = childpid;
result.internal = false;
return result;
}
setpgid(0, pgid != -1 ? pgid : 0);
if ( foreground_shell && pgid == -1 )
{
sigset_t oldset, sigttou;
sigemptyset(&sigttou);
sigaddset(&sigttou, SIGTTOU);
sigprocmask(SIG_BLOCK, &sigttou, &oldset);
tcsetpgrp(0, getpgid(0));
sigprocmask(SIG_SETMASK, &oldset, NULL);
}
if ( pipein != 0 )
dup2(pipein, 0);
if ( pipeout != 1 )
dup2(pipeout, 1);
for ( size_t i = 0; i < varsc; i++ )
{
char* key = varsv[i];
char* eq = strchr(key, '=');
if ( !eq )
continue;
*eq = '\0';
char* value = eq + 1;
int ret = setenv(key, value, 1);
*eq = '=';
if ( ret < 0 )
{
error(0, errno, "setenv");
status = 1;
}
}
execvp(argv[0], argv);
if ( interactive && errno == ENOENT )
{
int errno_saved = errno;
execlp("command-not-found", "command-not-found", argv[0], (const char*) NULL);
errno = errno_saved;
}
error(127, errno, "%s", argv[0]);
__builtin_unreachable();
}
int run_tokens(char** tokens,
size_t tokens_count,
bool interactive,
bool exit_on_error,
bool* script_exited)
{
size_t cmdnext = 0;
size_t cmdstart;
size_t cmdend;
int pipein = 0;
int pipeout = 1;
int pipeinnext = 0;
const char* execmode;
pid_t pgid = -1;
bool short_circuited_and = false;
bool short_circuited_or = false;
// Collect any pending zombie processes.
while ( 0 < waitpid(-1, NULL, WNOHANG) );
readcmd:
cmdstart = cmdnext;
if ( cmdstart == tokens_count )
return status;
for ( cmdend = cmdstart; cmdend < tokens_count; cmdend++ )
{
const char* token = tokens[cmdend];
if ( strcmp(token, ";") == 0 ||
strcmp(token, "&") == 0 ||
strcmp(token, "&&") == 0 ||
strcmp(token, "|") == 0 ||
strcmp(token, "||") == 0 ||
false )
break;
}
if ( cmdend < tokens_count )
{
execmode = tokens[cmdend];
cmdnext = cmdend + 1;
}
else
{
execmode = ";";
cmdnext = cmdend;
}
if ( short_circuited_or )
{
if ( !strcmp(execmode, ";") ||
!strcmp(execmode, "&") )
{
short_circuited_and = false;
short_circuited_or = false;
}
goto readcmd;
}
if ( short_circuited_and )
{
if ( !strcmp(execmode, ";") ||
!strcmp(execmode, "&") ||
!strcmp(execmode, "||") )
short_circuited_and = false;
goto readcmd;
}
if ( strcmp(execmode, "|") == 0 )
{
int pipes[2];
if ( pipe2(pipes, O_CLOEXEC) < 0 )
{
error(0, errno, "pipe");
if ( !interactive || exit_on_error )
*script_exited = true;
return status = 1;
}
else
{
if ( pipeout != 1 )
close(pipeout);
pipeout = pipes[1];
if ( pipeinnext != 0 )
close(pipeinnext);
pipeinnext = pipes[0];
}
}
struct execute_result result =
execute(tokens + cmdstart,
cmdend - cmdstart,
interactive,
pipein,
pipeout,
pgid);
if ( !result.internal && pgid == -1 )
pgid = result.pid;
if ( pipein != 0 )
{
close(pipein);
pipein = 0;
}
if ( pipeout != 1 )
{
close(pipeout);
pipeout = 1;
}
if ( pipeinnext != 0 )
{
pipein = pipeinnext;
pipeinnext = 0;
}
if ( result.critical )
{
if ( !interactive || exit_on_error )
*script_exited = true;
return status = result.internal_status;
}
if ( result.exited )
{
*script_exited = true;
return status = result.internal_status;
}
if ( strcmp(execmode, "&") == 0 )
{
// TODO: We probably shouldn't have made the progress group foreground
// as that may have side effects if a process checks for this
// behavior and then unexpectedly the shell takes back support
// without the usual ^Z mechanism.
sigset_t oldset, sigttou;
sigemptyset(&sigttou);
sigaddset(&sigttou, SIGTTOU);
sigprocmask(SIG_BLOCK, &sigttou, &oldset);
tcsetpgrp(0, getpgid(0));
sigprocmask(SIG_SETMASK, &oldset, NULL);
pgid = -1;
status = 0;
goto readcmd;
}
if ( strcmp(execmode, "|") == 0 )
goto readcmd;
if ( result.internal )
{
status = result.internal_status;
}
else
{
int exitstatus;
if ( waitpid(result.pid, &exitstatus, 0) < 0 )
{
error(0, errno, "waitpid");
if ( !interactive || exit_on_error )
*script_exited = true;
status = 1;
return status;
}
sigset_t oldset, sigttou;
sigemptyset(&sigttou);
sigaddset(&sigttou, SIGTTOU);
sigprocmask(SIG_BLOCK, &sigttou, &oldset);
tcsetpgrp(0, getpgid(0));
sigprocmask(SIG_SETMASK, &oldset, NULL);
if ( WIFSIGNALED(exitstatus) && WTERMSIG(exitstatus) == SIGINT )
printf("^C\n");
else if ( WIFSIGNALED(exitstatus) && WTERMSIG(exitstatus) != SIGPIPE )
printf("%s\n", strsignal(WTERMSIG(exitstatus)));
status = WEXITSTATUS(exitstatus);
}
pgid = -1;
if ( !strcmp(execmode, "&&") )
{
if ( status != 0 )
short_circuited_and = true;
}
else if ( !strcmp(execmode, "||") )
{
if ( status == 0 )
short_circuited_or = true;
}
else if ( exit_on_error && status != 0 )
{
*script_exited = true;
return status;
}
goto readcmd;
}
int run_command(char* command,
bool interactive,
bool exit_on_error,
bool* script_exited)
{
int result;
char** tokens = NULL;
size_t tokens_used = 0;
size_t tokens_length = 0;
enum sh_tokenize_result tokenize_result =
sh_tokenize(command, &tokens, &tokens_used, &tokens_length);
if ( tokenize_result == SH_TOKENIZE_RESULT_OK )
{
result = run_tokens(tokens, tokens_used, interactive, exit_on_error,
script_exited);
}
else
{
if ( !interactive )
*script_exited = true;
result = 255;
}
for ( size_t i = 0; i < tokens_used; i++ )
free(tokens[i]);
free(tokens);
return result;
}
bool does_line_editing_need_another_line(void* ctx, const char* line)
{
(void) ctx;
return !is_shell_input_ready(line);
}
bool is_outermost_shell(void)
{
const char* shlvl_str = getenv("SHLVL");
if ( !shlvl_str )
return true;
return atol(shlvl_str) <= 1;
}
void on_trap_eof(void* edit_state_ptr)
{
if ( is_outermost_shell() )
return;
struct edit_line* edit_state = (struct edit_line*) edit_state_ptr;
edit_line_type_codepoint(edit_state, L'e');
edit_line_type_codepoint(edit_state, L'x');
edit_line_type_codepoint(edit_state, L'i');
edit_line_type_codepoint(edit_state, L't');
}
bool is_usual_char_for_completion(char c)
{
return !isspace((unsigned char) c) &&
c != ';' && c != '&' && c != '|' &&
c != '<' && c != '>' && c != '#' && c != '$';
}
size_t do_complete(char*** completions_ptr,
size_t* used_before_ptr,
size_t* used_after_ptr,
void* ctx,
const char* partial,
size_t complete_at)
{
(void) ctx;
size_t used_before = 0;
size_t used_after = 0;
while ( complete_at - used_before &&
is_usual_char_for_completion(partial[complete_at - (used_before+1)]) )
used_before++;
#if 0
while ( partial[complete_at + used_after] &&
is_usual_char_for_completion(partial[complete_at + used_after]) )
used_after++;
#endif
enum complete_type
{
COMPLETE_TYPE_FILE,
COMPLETE_TYPE_EXECUTABLE,
COMPLETE_TYPE_DIRECTORY,
COMPLETE_TYPE_PROGRAM,
COMPLETE_TYPE_VARIABLE,
};
enum complete_type complete_type = COMPLETE_TYPE_FILE;
if ( complete_at - used_before && partial[complete_at - used_before-1] == '$' )
{
complete_type = COMPLETE_TYPE_VARIABLE;
used_before++;
}
else
{
size_t type_offset = complete_at - used_before;
while ( type_offset && isspace((unsigned char) partial[type_offset-1]) )
type_offset--;
if ( 2 <= type_offset &&
strncmp(partial + type_offset - 2, "cd", 2) == 0 &&
(type_offset == 2 || !is_usual_char_for_completion(partial[type_offset-2-1])) )
complete_type = COMPLETE_TYPE_DIRECTORY;
else if ( !type_offset ||
partial[type_offset-1] == ';' ||
partial[type_offset-1] == '&' ||
partial[type_offset-1] == '|' )
{
if ( memchr(partial + complete_at - used_before, '/', used_before) )
complete_type = COMPLETE_TYPE_EXECUTABLE;
else
complete_type = COMPLETE_TYPE_PROGRAM;
}
}
char** completions = NULL;
size_t completions_count = 0;
size_t completions_length = 0;
if ( complete_type == COMPLETE_TYPE_PROGRAM ) do
{
for ( size_t i = 0; builtin_commands[i]; i++ )
{
const char* builtin = builtin_commands[i];
if ( strncmp(builtin, partial + complete_at - used_before, used_before) != 0 )
continue;
// TODO: Add allocation check!
array_add((void***) &completions,
&completions_count,
&completions_length,
strdup(builtin + used_before));
}
char* path = strdup_safe(getenv("PATH"));
if ( !path )
{
complete_type = COMPLETE_TYPE_FILE;
break;
}
char* path_input = path;
char* component;
while ( (component = strsep(&path_input, ":")) )
{
DIR* dir;
if ( (dir = opendir(component)) )
{
struct dirent* entry;
while ( (entry = readdir(dir)) )
{
if ( strncmp(entry->d_name, partial + complete_at - used_before, used_before) != 0 )
continue;
if ( used_before == 0 && entry->d_name[0] == '.' )
continue;
// TODO: Add allocation check!
array_add((void***) &completions,
&completions_count,
&completions_length,
strdup(entry->d_name + used_before));
}
closedir(dir);
}
}
free(path);
} while ( false );
if ( complete_type == COMPLETE_TYPE_FILE ||
complete_type == COMPLETE_TYPE_EXECUTABLE ||
complete_type == COMPLETE_TYPE_DIRECTORY ) do
{
const char* pattern = partial + complete_at - used_before;
size_t pattern_length = used_before;
char* dirpath_alloc = NULL;
const char* dirpath;
if ( !memchr(pattern, '/', pattern_length) )
dirpath = ".";
else if ( pattern_length && pattern[pattern_length-1] == '/' )
{
dirpath_alloc = strndup(pattern, pattern_length);
if ( !dirpath_alloc )
break;
dirpath = dirpath_alloc;
pattern += pattern_length;
pattern_length = 0;
}
else
{
dirpath_alloc = strndup(pattern, pattern_length);
if ( !dirpath_alloc )
break;
dirpath = dirname(dirpath_alloc);
const char* last_slash = (const char*) memrchr(pattern, '/', pattern_length);
size_t last_slash_offset = (uintptr_t) last_slash - (uintptr_t) pattern;
pattern += last_slash_offset + 1;
pattern_length -= last_slash_offset + 1;
}
used_before = pattern_length;
DIR* dir = opendir(dirpath);
if ( !dir )
{
free(dirpath_alloc);
break;
}
struct dirent* entry;
while ( (entry = readdir(dir)) )
{
if ( strncmp(entry->d_name, pattern, pattern_length) != 0 )
continue;
if ( pattern_length == 0 && entry->d_name[0] == '.' )
continue;
struct stat st;
bool is_directory = entry->d_type == DT_DIR ||
(entry->d_type == DT_UNKNOWN &&
!fstatat(dirfd(dir), entry->d_name, &st, 0) &&
S_ISDIR(st.st_mode));
bool is_executable = complete_type == COMPLETE_TYPE_EXECUTABLE &&
!fstatat(dirfd(dir), entry->d_name, &st, 0) &&
st.st_mode & 0111;
if ( complete_type == COMPLETE_TYPE_DIRECTORY && !is_directory )
continue;
if ( complete_type == COMPLETE_TYPE_EXECUTABLE &&
!(is_directory || is_executable) )
continue;
size_t name_length = strlen(entry->d_name);
char* completion = (char*) malloc(name_length - pattern_length + 1 + 1);
if ( !completion )
continue;
strcpy(completion, entry->d_name + pattern_length);
if ( is_directory )
strcat(completion, "/");
// TODO: Add allocation check!
array_add((void***) &completions,
&completions_count,
&completions_length,
completion);
}
closedir(dir);
free(dirpath_alloc);
} while ( false );
if ( complete_type == COMPLETE_TYPE_VARIABLE ) do
{
const char* pattern = partial + complete_at - used_before + 1;
size_t pattern_length = used_before - 1;
if ( memchr(pattern, '=', pattern_length) )
break;
for ( size_t i = 0; environ[i]; i++ )
{
if ( strncmp(pattern, environ[i], pattern_length) != 0 )
continue;
const char* rest = environ[i] + pattern_length;
size_t equal_offset = strcspn(rest, "=");
if ( rest[equal_offset] != '=' )
continue;
// TODO: Add allocation check!
array_add((void***) &completions,
&completions_count,
&completions_length,
strndup(rest, equal_offset));
}
} while ( false );
*used_before_ptr = used_before;
*used_after_ptr = used_after;
return *completions_ptr = completions, completions_count;
}
struct sh_read_command
{
char* command;
bool abort_condition;
bool eof_condition;
bool error_condition;
};
void read_command_interactive(struct sh_read_command* sh_read_command)
{
update_env();
static struct edit_line edit_state; // static to preserve command history.
edit_state.in_fd = 0;
edit_state.out_fd = 1;
edit_state.check_input_incomplete_context = NULL;
edit_state.check_input_incomplete = does_line_editing_need_another_line;
edit_state.trap_eof_opportunity_context = &edit_state;
edit_state.trap_eof_opportunity = on_trap_eof;
edit_state.complete_context = NULL;
edit_state.complete = do_complete;
char* current_dir = get_current_dir_name();
const char* print_username = getlogin();
if ( !print_username )
print_username = getuid() == 0 ? "root" : "?";
char hostname[HOST_NAME_MAX + 1];
if ( gethostname(hostname, sizeof(hostname)) < 0 )
strlcpy(hostname, "(none)", sizeof(hostname));
const char* print_hostname = hostname;
const char* print_dir = current_dir ? current_dir : "?";
const char* home_dir = getenv_safe("HOME");
const char* print_dir_1 = print_dir;
const char* print_dir_2 = "";
char prompt_char = getuid() == 0 ? '#' : '$';
size_t home_dir_len = strlen(home_dir);
if ( home_dir_len && strncmp(print_dir, home_dir, home_dir_len) == 0 )
{
print_dir_1 = "~";
print_dir_2 = print_dir + home_dir_len;
}
char* ps1;
asprintf(&ps1, "\e[32m%s@%s \e[36m%s%s %c\e[37m ",
print_username,
print_hostname,
print_dir_1,
print_dir_2,
prompt_char);
free(current_dir);
edit_state.ps1 = ps1;
edit_state.ps2 = "> ";
edit_line(&edit_state);
free(ps1);
if ( edit_state.abort_editing )
{
sh_read_command->abort_condition = true;
return;
}
if ( edit_state.eof_condition )
{
sh_read_command->eof_condition = true;
return;
}
char* command = edit_line_result(&edit_state);
assert(command);
sh_read_command->command = command;
}
void read_command_non_interactive(struct sh_read_command* sh_read_command,
FILE* fp)
{
int fd = fileno(fp);
size_t command_used = 0;
size_t command_length = 1024;
char* command = (char*) malloc(command_length + 1);
if ( !command )
error(64, errno, "malloc");
command[0] = '\0';
while ( true )
{
char c;
if ( 0 <= fd )
{
ssize_t bytes_read = read(fd, &c, sizeof(c));
if ( bytes_read < 0 )
{
sh_read_command->error_condition = true;
free(command);
return;
}
else if ( bytes_read == 0 )
{
if ( command_used == 0 )
{
sh_read_command->eof_condition = true;
free(command);
return;
}
else
{
c = '\n';
}
}
else
{
assert(bytes_read == 1);
if ( c == '\0' )
continue;
}
}
else
{
int ic = fgetc(fp);
if ( ic == EOF && ferror(fp) )
{
sh_read_command->error_condition = true;
free(command);
return;
}
else if ( ic == EOF )
{
if ( command_used == 0 )
{
sh_read_command->eof_condition = true;
free(command);
return;
}
else
{
c = '\n';
}
}
else
{
c = (char) (unsigned char) ic;
if ( c == '\0' )
continue;
}
}
if ( c == '\n' && is_shell_input_ready(command) )
break;
if ( command_used == command_length )
{
size_t new_length = command_length * 2;
char* new_command = (char*) realloc(command, new_length + 1);
if ( !new_command )
error(64, errno, "realloc");
command = new_command;
command_length = new_length;
}
command[command_used++] = c;
command[command_used] = '\0';
}
sh_read_command->command = command;
}
int run(FILE* fp,
const char* fp_name,
bool interactive,
bool exit_on_error,
bool* script_exited,
int status)
{
// TODO: The interactive read code should cope when the input is not a
// terminal; it should print the prompt and then read normally without
// any line editing features.
if ( !isatty(fileno(fp)) || !foreground_shell )
interactive = false;
while ( true )
{
struct sh_read_command sh_read_command;
memset(&sh_read_command, 0, sizeof(sh_read_command));
if ( interactive )
read_command_interactive(&sh_read_command);
else
read_command_non_interactive(&sh_read_command, fp);
if ( sh_read_command.abort_condition )
continue;
if ( sh_read_command.eof_condition )
{
if ( interactive && is_outermost_shell() )
{
printf("Type exit to close the outermost shell.\n");
continue;
}
break;
}
if ( sh_read_command.error_condition )
{
error(0, errno, "read: %s", fp_name);
return *script_exited = true, 2;
}
status = run_command(sh_read_command.command, interactive,
exit_on_error, script_exited);
free(sh_read_command.command);
if ( *script_exited || (status == 0 && exit_on_error) )
break;
}
return status;
}
static void compact_arguments(int* argc, char*** argv)
{
for ( int i = 0; i < *argc; i++ )
{
while ( i < *argc && !(*argv)[i] )
{
for ( int n = i; n < *argc; n++ )
(*argv)[n] = (*argv)[n+1];
(*argc)--;
}
}
}
static void help(FILE* fp, const char* argv0)
{
fprintf(fp, "Usage: %s [OPTION...] [SCRIPT [ARGUMENT...]]\n", argv0);
fprintf(fp, " or: %s [OPTION...] -c COMMAND [ARGUMENT...]\n", argv0);
fprintf(fp, " or: %s [OPTION...] -s [ARGUMENT...]\n", argv0);
#if 0
fprintf(fp, " -a, +a set -a\n");
fprintf(fp, " -b, +b set -b\n");
#endif
fprintf(fp, " -c execute the first operand as the command\n");
#if 0
fprintf(fp, " -C, +C set -C\n");
fprintf(fp, " -e, +e set -e\n");
fprintf(fp, " -f, +f set -f\n");
fprintf(fp, " -h, +h set -h\n");
#endif
fprintf(fp, " -i shell is interactive\n");
#if 0
fprintf(fp, " -m, +m set -m\n");
fprintf(fp, " -n, +n set -n\n");
fprintf(fp, " -o OPTION set -o OPTION\n");
fprintf(fp, " +o OPTION set +o OPTION\n");
#endif
fprintf(fp, " -s read commands from the standard input\n");
#if 0
fprintf(fp, " -u, +u set -u\n");
fprintf(fp, " -v, +v set -v\n");
fprintf(fp, " -x, +x set -x\n");
#endif
fprintf(fp, " --help display this help and exit\n");
fprintf(fp, " --version output version information and exit\n");
}
static void version(FILE* fp, const char* argv0)
{
fprintf(fp, "%s (Sortix) %s\n", argv0, VERSIONSTR);
}
int main(int argc, char* argv[])
{
setlocale(LC_ALL, "");
foreground_shell = isatty(0) && tcgetpgrp(0) == getpgid(0);
// TODO: Canonicalize argv[0] if it contains a slash and isn't absolute?
const char* env_pwd;
if ( (env_pwd = getenv("PWD")) )
{
if ( !is_proper_absolute_path(env_pwd) )
{
unsetenv("PWD");
char* real_pwd = get_current_dir_name();
if ( real_pwd )
setenv("PWD", real_pwd, 1);
free(real_pwd);
}
}
bool flag_c_first_operand_is_command = false;
bool flag_e_exit_on_error = false;
bool flag_i_interactive = false;
bool flag_s_stdin = false;
const char* argv0 = argv[0];
for ( int i = 1; i < argc; i++ )
{
const char* arg = argv[i];
if ( (arg[0] != '-' && arg[0] != '+') || !arg[1] )
break; // Intentionally not continue and note '+' support.
argv[i] = NULL;
if ( !strcmp(arg, "--") )
break;
if ( arg[0] == '+' )
{
char c;
while ( (c = *++arg) ) switch ( c )
{
case 'e': flag_e_exit_on_error = false; break;
default:
fprintf(stderr, "%s: unknown option -- '%c'\n", argv0, c);
help(stderr, argv0);
exit(1);
}
}
else if ( arg[1] != '-' )
{
char c;
while ( (c = *++arg) ) switch ( c )
{
case 'c': flag_c_first_operand_is_command = true; break;
case 'e': flag_e_exit_on_error = true; break;
case 'i': flag_i_interactive = true; break;
case 's': flag_s_stdin = true; break;
default:
fprintf(stderr, "%s: unknown option -- '%c'\n", argv0, c);
help(stderr, argv0);
exit(1);
}
}
else if ( !strcmp(arg, "--help") )
help(stdout, argv0), exit(0);
else if ( !strcmp(arg, "--version") )
version(stdout, argv0), exit(0);
else
{
fprintf(stderr, "%s: unknown option: %s\n", argv0, arg);
help(stderr, argv0);
exit(1);
}
}
compact_arguments(&argc, &argv);
if ( getenv("SHLVL") )
{
long shlvl = atol(getenv("SHLVL"));
if ( shlvl < 1 )
shlvl = 1;
else if ( shlvl < LONG_MAX )
shlvl++;
char shlvl_string[sizeof(long) * 3];
snprintf(shlvl_string, sizeof(shlvl_string), "%li", shlvl);
setenv("SHLVL", shlvl_string, 1);
}
else
{
setenv("SHLVL", "1", 1);
}
char pidstr[3 * sizeof(pid_t)];
char ppidstr[3 * sizeof(pid_t)];
snprintf(pidstr, sizeof(pidstr), "%ji", (intmax_t) getpid());
snprintf(ppidstr, sizeof(ppidstr), "%ji", (intmax_t) getppid());
setenv("SHELL", argv[0], 1);
setenv("$", pidstr, 1);
setenv("PPID", ppidstr, 1);
setenv("?", "0", 1);
setenv("0", argv[0], 1);
bool script_exited = false;
int status = 0;
if ( flag_c_first_operand_is_command )
{
if ( argc <= 1 )
error(2, 0, "option -c expects an operand");
for ( int i = 2; i < argc; i++ )
{
char varname[sizeof(int) * 3];
snprintf(varname, sizeof(varname), "%i", i - 2);
setenv(varname, argv[i], 1);
}
const char* command = argv[1];
size_t command_length = strlen(command);
FILE* fp = fmemopen((void*) command, command_length, "r");
if ( !fp )
error(2, errno, "fmemopen");
status = run(fp, "<command-line>", false, flag_e_exit_on_error,
&script_exited, status);
fclose(fp);
if ( script_exited || (status != 0 && flag_e_exit_on_error) )
exit(status);
if ( flag_s_stdin )
{
bool is_interactive = flag_i_interactive || isatty(fileno(stdin));
status = run(stdin, "<stdin>", is_interactive, flag_e_exit_on_error,
&script_exited, status);
if ( script_exited || (status != 0 && flag_e_exit_on_error) )
exit(status);
}
}
else if ( flag_s_stdin )
{
for ( int i = 1; i < argc; i++ )
{
char varname[sizeof(int) * 3];
snprintf(varname, sizeof(varname), "%i", i - 1);
setenv(varname, argv[i], 1);
}
bool is_interactive = flag_i_interactive || isatty(fileno(stdin));
status = run(stdin, "<stdin>", is_interactive, flag_e_exit_on_error,
&script_exited, status);
if ( script_exited || (status != 0 && flag_e_exit_on_error) )
exit(status);
}
else if ( 2 <= argc )
{
for ( int i = 1; i < argc; i++ )
{
char varname[sizeof(int) * 3];
snprintf(varname, sizeof(varname), "%i", i - 1);
setenv(varname, argv[i], 1);
}
const char* path = argv[1];
FILE* fp = fopen(path, "r");
if ( !fp )
error(127, errno, "%s", path);
status = run(fp, path, false, flag_e_exit_on_error, &script_exited,
status);
fclose(fp);
if ( script_exited || (status != 0 && flag_e_exit_on_error) )
exit(status);
}
else
{
bool is_interactive = flag_i_interactive || isatty(fileno(stdin));
status = run(stdin, "<stdin>", is_interactive, flag_e_exit_on_error,
&script_exited, status);
if ( script_exited || (status != 0 && flag_e_exit_on_error) )
exit(status);
}
return 0;
}