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Diffstat (limited to 'posix/wordexp.c')
| -rw-r--r-- | posix/wordexp.c | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/posix/wordexp.c b/posix/wordexp.c new file mode 100644 index 0000000..1922e44 --- /dev/null +++ b/posix/wordexp.c @@ -0,0 +1,184 @@ +/* Copyright (C) 1992 Free Software Foundation, Inc. +This file is part of the GNU C Library. + +The GNU C Library is free software; you can redistribute it and/or +modify it under the terms of the GNU Library General Public License as +published by the Free Software Foundation; either version 2 of the +License, or (at your option) any later version. + +The GNU C Library is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +#include <ansidecl.h> +#include <sys/types.h> +#include <wordexp.h> +#include <stdio.h> +#include <unistd.h> +#include <sys/wait.h> +#include <signal.h> + + +/* We do word expansion with a pipe to the shell. + The shell command `sh [-P] [-u] -w "words ..."' expands words. + If -P, command substitution is an error. + If -u, reference to an undefined variable is an error. + The shell writes on its stdout: + %u\0 Number of words. + %u\0 Number of bytes in all words together (not counting \0s). + word1\0 + word2\0 + ... + wordN\0 + */ + +#define SHELL_PATH "/bin/sh" +#define SHELL_NAME "sh" + + +int +DEFUN(wordexp, (string, pwordexp, flags), + CONST char *string AND wordexp_t *pwordexp AND int flags) +{ + int error; + pid_t pid; + int d[2]; + int status; + + FILE *f; + size_t wordc, start, buflen; + char *buf; + + /* Create the pipe through which we will communicate to the shell. */ + if (pipe (d) < 0) + return -1; + + pid = fork (); + if (pid < 0) + return -1; + + if (pid == 0) + { + /* Child. Run the shell. */ + + CONST char *argv[5]; + + close (d[STDIN_FILENO]); + dup2 (d[STDOUT_FILENO], STDOUT_FILENO); + if (!(flags & WRDE_SHOWERR)) + close (STDERR_FILENO); + + i = 0; + argv[i++] = SHELL_NAME; + if (flags & WRDE_NOCMD) + argv[i++] = "-P"; + if (flags & WRDE_UNDEF) + argv[i++] = "-u"; + argv[i++] = "-w"; + argv[i++] = string; + argv[i++] = NULL; + + execv (SHELL_PATH, argv); + _exit (WRDE_NOSPACE); + } + + /* Parent. */ + + buf = NULL; + error = WRDE_NOSPACE; + + close (d[STDOUT_FILENO]); + f = fdopen (d[STDIN_FILENO]); + if (f == NULL) + goto lose; + + /* Read the number of words and number of bytes from the shell. */ + if (fscanf (f, "%u", &wordc) != 1 || getc (f) != '\0' || + fscanf (f, "%u", &buflen) != 1 || getc (f) != '\0') + goto lose; + + /* Read the words from the shell, and wait for it to return. */ + buflen += wordc; + buf = malloc (buflen); + if (buf == NULL || + fread (buf, buflen, 1, f) != 1 || + waitpid (pid, &status, 0) != pid) + goto lose; + + if (WIFEXITED (status)) + { + if (WEXITSTATUS (status) != 0) + { + error = WEXITSTATUS (status); + goto lose; + } + } + else + goto lose; + + /* Pack the structure. */ + + start = 0; + if (flags & WRDE_DOOFFS) + start += pwordexp->we_offs; + if (flags & WRDE_APPEND) + start += pwordexp->we_wordc; + wordc = start + wordc + 1; + + if (flags & WRDE_APPEND) + wordv = (char **) realloc ((PTR) pwordexp->we_wordv, + wordc * sizeof (char *)); + else + wordv = (char **) malloc (wordc * sizeof (char *)); + if (wordv == NULL) + goto lose; + + if (flags & WRDE_DOOFFS) + for (i = 0; i < pwordexp->we_offs; ++i) + wordv[i] = NULL; + + for (i = start; i < wordc; ++i) + { + pwordexp->we_wordv[i] = buf; + buf = strchr (buf, '\0') + 1; + } + wordv[i] = NULL; + + if (flags & WRDE_REUSE) + { + free (pwordexp->we_wordv[0]); + if (!(flags & WRDE_APPEND)) + free (pwordexp->we_wordv); + } + + pwordexp->we_wordc = wordc; + pwordexp->we_wordv = wordv; + + return 0; + + lose: + { + int save; + save = errno; + (void) kill (pid, SIGKILL); + free (buf); + (void) waitpid (pid, (int *) NULL, 0); + errno = save; + return error; + } +} + + +void +DEFUN(wordexp, (pwordexp), wordexp_t *pwordexp) +{ + /* All the other elts point into the first. */ + free (pwordexp->we_wordv[0]); + free (pwordexp->we_wordv); +} |