static char *exec_wrapper;
-/* Break up SCRATCH into an argument vector suitable for passing to
- execvp and store it in ARGV. E.g., on "run a b c d" this routine
- would get as input the string "a b c d", and as output it would
- fill in ARGV with the four arguments "a", "b", "c", "d". */
+/* Build the argument vector for execv(3). */
-static void
-breakup_args (const std::string &scratch, std::vector<char *> &argv)
+class execv_argv
+{
+public:
+ /* EXEC_FILE is the file to run. ALLARGS is a string containing the
+ arguments to the program. If starting with a shell, SHELL_FILE
+ is the shell to run. Otherwise, SHELL_FILE is NULL. */
+ execv_argv (const char *exec_file, const std::string &allargs,
+ const char *shell_file);
+
+ /* Return a pointer to the built argv, in the type expected by
+ execv. The result is (only) valid for as long as this execv_argv
+ object is live. We return a "char **" because that's the type
+ that the execv functions expect. Note that it is guaranteed that
+ the execv functions do not modify the argv[] array nor the
+ strings to which the array point. */
+ char **argv ()
+ {
+ return const_cast<char **> (&m_argv[0]);
+ }
+
+private:
+ /* Disable copying. */
+ execv_argv (const execv_argv &) = delete;
+ void operator= (const execv_argv &) = delete;
+
+ /* Helper methods for constructing the argument vector. */
+
+ /* Used when building an argv for a straight execv call, without
+ going via the shell. */
+ void init_for_no_shell (const char *exec_file,
+ const std::string &allargs);
+
+ /* Used when building an argv for execing a shell that execs the
+ child program. */
+ void init_for_shell (const char *exec_file,
+ const std::string &allargs,
+ const char *shell_file);
+
+ /* The argument vector built. Holds non-owning pointers. Elements
+ either point to the strings passed to the execv_argv ctor, or
+ inside M_STORAGE. */
+ std::vector<const char *> m_argv;
+
+ /* Storage. In the no-shell case, this contains a copy of the
+ arguments passed to the ctor, split by '\0'. In the shell case,
+ this contains the quoted shell command. I.e., SHELL_COMMAND in
+ {"$SHELL" "-c", SHELL_COMMAND, NULL}. */
+ std::string m_storage;
+};
+
+/* Create argument vector for straight call to execvp. Breaks up
+ ALLARGS into an argument vector suitable for passing to execvp and
+ stores it in M_ARGV. E.g., on "run a b c d" this routine would get
+ as input the string "a b c d", and as output it would fill in
+ M_ARGV with the four arguments "a", "b", "c", "d". Each argument
+ in M_ARGV points to a substring of a copy of ALLARGS stored in
+ M_STORAGE. */
+
+void
+execv_argv::init_for_no_shell (const char *exec_file,
+ const std::string &allargs)
{
- for (size_t cur_pos = 0; cur_pos < scratch.size ();)
+
+ /* Save/work with a copy stored in our storage. The pointers pushed
+ to M_ARGV point directly into M_STORAGE, which is modified in
+ place with the necessary NULL terminators. This avoids N heap
+ allocations and string dups when 1 is sufficient. */
+ std::string &args_copy = m_storage = allargs;
+
+ m_argv.push_back (exec_file);
+
+ for (size_t cur_pos = 0; cur_pos < args_copy.size ();)
{
/* Skip whitespace-like chars. */
- std::size_t pos = scratch.find_first_not_of (" \t\n", cur_pos);
+ std::size_t pos = args_copy.find_first_not_of (" \t\n", cur_pos);
if (pos != std::string::npos)
cur_pos = pos;
/* Find the position of the next separator. */
- std::size_t next_sep = scratch.find_first_of (" \t\n", cur_pos);
+ std::size_t next_sep = args_copy.find_first_of (" \t\n", cur_pos);
- /* No separator found, which means this is the last
- argument. */
if (next_sep == std::string::npos)
- next_sep = scratch.size ();
+ {
+ /* No separator found, which means this is the last
+ argument. */
+ next_sep = args_copy.size ();
+ }
+ else
+ {
+ /* Replace the separator with a terminator. */
+ args_copy[next_sep++] = '\0';
+ }
- char *arg = savestring (scratch.c_str () + cur_pos, next_sep - cur_pos);
- argv.push_back (arg);
+ m_argv.push_back (&args_copy[cur_pos]);
cur_pos = next_sep;
}
/* NULL-terminate the vector. */
- argv.push_back (NULL);
+ m_argv.push_back (NULL);
}
-/* When executing a command under the given shell, return non-zero if
- the '!' character should be escaped when embedded in a quoted
+/* When executing a command under the given shell, return true if the
+ '!' character should be escaped when embedded in a quoted
command-line argument. */
-static int
+static bool
escape_bang_in_quoted_argument (const char *shell_file)
{
- const int shell_file_len = strlen (shell_file);
+ size_t shell_file_len = strlen (shell_file);
/* Bang should be escaped only in C Shells. For now, simply check
that the shell name ends with 'csh', which covers at least csh
and tcsh. This should be good enough for now. */
if (shell_file_len < 3)
- return 0;
+ return false;
if (shell_file[shell_file_len - 3] == 'c'
&& shell_file[shell_file_len - 2] == 's'
&& shell_file[shell_file_len - 1] == 'h')
- return 1;
+ return true;
- return 0;
+ return false;
+}
+
+/* See declaration. */
+
+execv_argv::execv_argv (const char *exec_file,
+ const std::string &allargs,
+ const char *shell_file)
+{
+ if (shell_file == NULL)
+ init_for_no_shell (exec_file, allargs);
+ else
+ init_for_shell (exec_file, allargs, shell_file);
+}
+
+/* See declaration. */
+
+void
+execv_argv::init_for_shell (const char *exec_file,
+ const std::string &allargs,
+ const char *shell_file)
+{
+ /* We're going to call a shell. */
+ bool escape_bang = escape_bang_in_quoted_argument (shell_file);
+
+ /* We need to build a new shell command string, and make argv point
+ to it. So build it in the storage. */
+ std::string &shell_command = m_storage;
+
+ shell_command = "exec ";
+
+ /* Add any exec wrapper. That may be a program name with arguments,
+ so the user must handle quoting. */
+ if (exec_wrapper)
+ {
+ shell_command += exec_wrapper;
+ shell_command += ' ';
+ }
+
+ /* Now add exec_file, quoting as necessary. */
+
+ /* Quoting in this style is said to work with all shells. But csh
+ on IRIX 4.0.1 can't deal with it. So we only quote it if we need
+ to. */
+ bool need_to_quote;
+ const char *p = exec_file;
+ while (1)
+ {
+ switch (*p)
+ {
+ case '\'':
+ case '!':
+ case '"':
+ case '(':
+ case ')':
+ case '$':
+ case '&':
+ case ';':
+ case '<':
+ case '>':
+ case ' ':
+ case '\n':
+ case '\t':
+ need_to_quote = true;
+ goto end_scan;
+
+ case '\0':
+ need_to_quote = false;
+ goto end_scan;
+
+ default:
+ break;
+ }
+ ++p;
+ }
+ end_scan:
+ if (need_to_quote)
+ {
+ shell_command += '\'';
+ for (p = exec_file; *p != '\0'; ++p)
+ {
+ if (*p == '\'')
+ shell_command += "'\\''";
+ else if (*p == '!' && escape_bang)
+ shell_command += "\\!";
+ else
+ shell_command += *p;
+ }
+ shell_command += '\'';
+ }
+ else
+ shell_command += exec_file;
+
+ shell_command += ' ' + allargs;
+
+ /* If we decided above to start up with a shell, we exec the shell.
+ "-c" says to interpret the next arg as a shell command to
+ execute, and this command is "exec <target-program> <args>". */
+ m_argv.reserve (4);
+ m_argv.push_back (shell_file);
+ m_argv.push_back ("-c");
+ m_argv.push_back (shell_command.c_str ());
+ m_argv.push_back (NULL);
}
/* See inferior.h. */
static char *shell_file;
static const char *exec_file;
char **save_our_env;
- int shell = 0;
- std::vector<char *> argv;
const char *inferior_io_terminal = get_inferior_io_terminal ();
struct inferior *inf;
int i;
/* 'startup_with_shell' is declared in inferior.h and bound to the
"set startup-with-shell" option. If 0, we'll just do a
fork/exec, no shell, so don't bother figuring out what shell. */
- shell_file = shell_file_arg;
if (startup_with_shell)
{
+ shell_file = shell_file_arg;
/* Figure out what shell to start up the user program under. */
if (shell_file == NULL)
shell_file = getenv ("SHELL");
if (shell_file == NULL)
shell_file = default_shell_file;
- shell = 1;
- }
-
- if (!shell)
- {
- /* We're going to call execvp. Create argument vector. */
- argv.push_back (xstrdup (exec_file));
- breakup_args (allargs, argv);
}
else
- {
- /* We're going to call a shell. */
- std::string shell_command;
- const char *p;
- int need_to_quote;
- const int escape_bang = escape_bang_in_quoted_argument (shell_file);
-
- shell_command = std::string ("exec ");
-
- /* Add any exec wrapper. That may be a program name with arguments, so
- the user must handle quoting. */
- if (exec_wrapper)
- {
- shell_command += exec_wrapper;
- shell_command += ' ';
- }
+ shell_file = NULL;
- /* Now add exec_file, quoting as necessary. */
-
- /* Quoting in this style is said to work with all shells. But
- csh on IRIX 4.0.1 can't deal with it. So we only quote it if
- we need to. */
- p = exec_file;
- while (1)
- {
- switch (*p)
- {
- case '\'':
- case '!':
- case '"':
- case '(':
- case ')':
- case '$':
- case '&':
- case ';':
- case '<':
- case '>':
- case ' ':
- case '\n':
- case '\t':
- need_to_quote = 1;
- goto end_scan;
-
- case '\0':
- need_to_quote = 0;
- goto end_scan;
-
- default:
- break;
- }
- ++p;
- }
- end_scan:
- if (need_to_quote)
- {
- shell_command += '\'';
- for (p = exec_file; *p != '\0'; ++p)
- {
- if (*p == '\'')
- shell_command += "'\\''";
- else if (*p == '!' && escape_bang)
- shell_command += "\\!";
- else
- shell_command += *p;
- }
- shell_command += '\'';
- }
- else
- shell_command += exec_file;
-
- shell_command += " " + allargs;
-
- /* If we decided above to start up with a shell, we exec the
- shell, "-c" says to interpret the next arg as a shell command
- to execute, and this command is "exec <target-program>
- <args>". We xstrdup all the strings here because they will
- be free'd later in the code. */
- argv.push_back (xstrdup (shell_file));
- argv.push_back (xstrdup ("-c"));
- argv.push_back (xstrdup (shell_command.c_str ()));
- argv.push_back (NULL);
- }
+ /* Build the argument vector. */
+ execv_argv child_argv (exec_file, allargs, shell_file);
/* Retain a copy of our environment variables, since the child will
replace the value of environ and if we're vforked, we have to
path to find $SHELL. Rich Pixley says so, and I agree. */
environ = env;
+ char **argv = child_argv.argv ();
+
if (exec_fun != NULL)
(*exec_fun) (argv[0], &argv[0], env);
else
_exit (0177);
}
- free_vector_argv (argv);
-
/* Restore our environment in case a vforked child clob'd it. */
environ = save_our_env;
projects / binutils-gdb.git / commitdiff