diff options
Diffstat (limited to 'posix')
| -rw-r--r-- | posix/wordexp.c | 1624 |
1 files changed, 1507 insertions, 117 deletions
diff --git a/posix/wordexp.c b/posix/wordexp.c index 52869fe1d3..b204f653b5 100644 --- a/posix/wordexp.c +++ b/posix/wordexp.c @@ -1,5 +1,7 @@ -/* Copyright (C) 1992, 1997 Free Software Foundation, Inc. +/* POSIX.2 wordexp implementation. + Copyright (C) 1997 Free Software Foundation, Inc. This file is part of the GNU C Library. + Contributed by Tim Waugh <tim@cyberelk.demon.co.uk>. 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 @@ -16,170 +18,1558 @@ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ -#include <sys/types.h> #include <wordexp.h> -#include <stdio.h> -#include <unistd.h> -#include <sys/wait.h> #include <signal.h> +#include <stdlib.h> +#include <pwd.h> +#include <sys/types.h> +#include <string.h> +#include <glob.h> +#include <ctype.h> +#include <sys/time.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <unistd.h> +#include <fcntl.h> +#include <sys/stat.h> +#include <paths.h> +#include <errno.h> +#include <assert.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 +/* + * This is a recursive-descent-style word expansion routine. + */ + +/* Some forward declarations */ +static int +parse_dollars (char **word, size_t *word_length, const char *words, + size_t *offset, int flags, wordexp_t *pwordexp); +static int +parse_backtick (char **word, size_t *word_length, const char *words, + size_t *offset, int flags, wordexp_t *pwordexp); + +static int +eval_expr (char *expr, int *result); + +/* The w_*() unctions manipulate word lists. */ + +static char* +w_extend (char *word, size_t *word_length, size_t by) +{ + /* Extend the allocated size of word by 'by' characters + * (from *word_length). */ + char* newword; + size_t new_length; -#define SHELL_PATH "/bin/sh" -#define SHELL_NAME "sh" + if (word == NULL) + *word_length = 0; + new_length = *word_length + by; + newword = realloc (word, 1 + new_length); + if (newword != NULL) + { + *word_length = new_length; -int -wordexp (string, pwordexp, flags) - const char *string; - wordexp_t *pwordexp; - int flags; + newword[*word_length] = 0; + } + return newword; +} + +static char* +w_addstr (char *word, size_t *word_length, const char *str) +{ + /* Add a string to 'word', allocating room for it. + */ + char* newword; + size_t new_length; + + if (word == NULL) + *word_length = '\0'; + + new_length = *word_length + strlen (str); + newword = realloc (word, 1 + new_length); + if (newword != NULL) + { + strcpy (&newword[*word_length], str); + *word_length = new_length; + } + return newword; +} + +static inline char* +w_addchar (char *word, size_t *word_length, char ch) +{ + /* Add a character to 'word', allocating room for it. + */ + char* newword = w_extend (word, word_length, 1); + + if (newword != NULL) + newword[*word_length - 1] = ch; + return newword; +} + +static int +w_addword (wordexp_t *pwordexp, char *word) +{ + /* Add a word to the wordlist */ + size_t num_p; + + num_p = 2 + pwordexp->we_wordc + pwordexp->we_offs; + pwordexp->we_wordv = realloc (pwordexp->we_wordv, sizeof (char *) * num_p); + if (pwordexp->we_wordv != NULL) + { + pwordexp->we_wordv[pwordexp->we_wordc++] = word; + pwordexp->we_wordv[pwordexp->we_wordc] = NULL; + return 0; + } + + return WRDE_NOSPACE; +} + +/* The parse_*() functions should leave *offset being the offset in 'words' + * to the last character processed. + */ + +static int +parse_backslash (char **word, size_t *word_length, const char *words, + size_t *offset) +{ + /* We are poised _at_ a backslash, not in quotes */ + + switch (words[1 + *offset]) + { + case 0: + /* Backslash is last character of input words */ + return WRDE_SYNTAX; + + case '\n': + ++(*offset); + break; + + default: + *word = w_addchar (*word, word_length, words[1 + *offset]); + if (*word == NULL) + return WRDE_NOSPACE; + + ++(*offset); + break; + } + + return 0; +} + +static int +parse_qtd_backslash (char **word, size_t *word_length, const char *words, + size_t *offset) +{ + /* We are poised _at_ a backslash, inside quotes */ + + switch (words[1 + *offset]) + { + case 0: + /* Backslash is last character of input words */ + return WRDE_SYNTAX; + + case '\n': + ++(*offset); + break; + + case '$': + case '`': + case '"': + case '\\': + *word = w_addchar (*word, word_length, words[1 + *offset]); + if (*word == NULL) + return WRDE_NOSPACE; + + (*offset)++; + break; + + default: + *word = w_extend (*word, word_length, 2); + if (*word == NULL) + return WRDE_NOSPACE; + + (*word)[*word_length - 1] = words[1 + *offset]; + (*word)[*word_length - 2] = words[*offset]; + (*offset)++; + break; + } + + return 0; +} + +static int +parse_tilde (char **word, size_t *word_length, const char *words, + size_t *offset, size_t wordc) +{ + /* We are poised _at_ a tilde */ + int i; + + if (*word_length != 0) + { + if (!((*word)[*word_length - 1] == '=' && wordc == 0)) + { + if (!((*word)[*word_length - 1] == ':' && + strchr(*word, '=') && wordc == 0)) + { + *word = w_addchar (*word, word_length, '~'); + return *word ? 0 : WRDE_NOSPACE; + } + } + } + + for (i = 1 + *offset; words[i]; i++) + { + if (words[i] == ':' || words[i] == '/' || words[i] == ' ' || + words[i] == '\t' || words[i] == 0 ) + break; + + if (words[i] == '\\') + { + *word = w_addchar (*word, word_length, '~'); + return *word ? 0 : WRDE_NOSPACE; + } + } + + if (i == 1 + *offset) + { + /* Tilde appears on its own */ + uid_t uid; + struct passwd pwd, *tpwd; + int buflen = 1000; + char* buffer = __alloca (buflen); + int result; + + uid = getuid (); + + while ((result = __getpwuid_r (uid, pwd, buffer, buflen, &tpwd)) != 0 + && errno == ERANGE) + { + buflen += 1000; + buffer = __alloca (buflen); + } + + if (result == 0 && pwd.pw_dir != NULL) + { + *word = w_addstr (*word, word_length, pwd.pw_dir); + if (*word == NULL) + return WRDE_NOSPACE; + } + else + { + *word = w_addchar (*word, word_length, '~'); + if (*word == NULL) + return WRDE_NOSPACE; + } + } + else + { + /* Look up user name in database to get home directory */ + uid_t uid; + char *user = strndup (&words[1 + *offset], i - *offset); + struct passwd pwd, *tpwd; + int buflen = 1000; + char* buffer = __alloca (buflen); + int result; + + while ((result = __getpwnam_r (uid, pwd, buffer, buflen, &tpwd)) != 0 + && errno == ERANGE) + { + buflen += 1000; + buffer = __alloca (buflen); + } + + if (result == 0 && pwd.pw_dir) + *word = w_addstr (*word, word_length, pwd.pw_dir); + else + { + /* (invalid login name) */ + *word = w_addchar (*word, word_length, '~'); + if (*word != NULL) + *word = w_addstr (*word, word_length, user); + } + + *offset = i - 1; + } + return *word ? 0 : WRDE_NOSPACE; +} + +static int +parse_glob (char **word, size_t *word_length, const char *words, + size_t *offset, int flags, wordexp_t *pwordexp, char *ifs) +{ + /* We are poised just after a '*' or a '{'. */ + int error; + glob_t globbuf; + int match; + char * matching_word; + + for (; words[*offset]; (*offset)++) + switch (words[*offset]) + { + case ' ': + case '\t': + break; + + case '$': + error = parse_dollars (word, word_length, words, offset, flags, + pwordexp); + if (error) + return error; + + continue; + + default: + if (ifs == NULL || strchr (ifs, words[*offset]) == NULL) + { + *word = w_addchar (*word, word_length, words[*offset]); + if (*word == NULL) + return WRDE_NOSPACE; + + continue; + } + + break; + } + + error = glob (*word, GLOB_NOCHECK, NULL, &globbuf); + + if (error != 0) + { + /* We can only run into memory problems. */ + assert (error == GLOB_NOSPACE); + + return WRDE_NOSPACE; + } + + if (ifs && !*ifs) + { + /* No field splitting allowed */ + *word_length = strlen (globbuf.gl_pathv[0]); + *word = realloc (*word, 1 + *word_length); + if (*word == NULL) + goto no_space; + + strcpy (*word, globbuf.gl_pathv[0]); + + for (match = 1; match < globbuf.gl_pathc; ++match) + { + *word = w_addchar (*word, word_length, ' '); + if (*word != NULL) + *word = w_addstr (*word, word_length, globbuf.gl_pathv[match]); + } + + /* Re-parse white space on return */ + globfree (&globbuf); + --(*offset); + return *word ? 0 : WRDE_NOSPACE; + } + + /* here ifs != "" */ + free (*word); + *word = NULL; + *word_length = 0; + + matching_word = malloc (1 + strlen (globbuf.gl_pathv[0])); + if (matching_word == NULL) + goto no_space; + + strcpy (matching_word, globbuf.gl_pathv[0]); + if (w_addword (pwordexp, matching_word) == WRDE_NOSPACE) + goto no_space; + + for (match = 1; match < globbuf.gl_pathc; ++match) + { + matching_word = malloc (1 + strlen (globbuf.gl_pathv[match])); + if (matching_word == NULL) + goto no_space; + + strcpy (matching_word, globbuf.gl_pathv[match]); + if (w_addword (pwordexp, matching_word) == WRDE_NOSPACE) + goto no_space; + } + + globfree (&globbuf); + + /* Re-parse white space on return */ + --(*offset); + return 0; + +no_space: + globfree (&globbuf); + return WRDE_NOSPACE; +} + +static int +parse_squote (char **word, size_t *word_length, const char *words, + size_t *offset) +{ + /* We are poised just after a single quote */ + for (; words[*offset]; ++(*offset)) + { + if (words[*offset] != '\'') + { + *word = w_addchar (*word, word_length, words[*offset]); + if (*word == NULL) + return WRDE_NOSPACE; + } + else return 0; + } + + /* Unterminated string */ + return WRDE_SYNTAX; +} + +/* Functions to evaluate an arithmetic expression */ +static int +eval_expr_val (char **expr, int *result) { + int sgn = +1; + char *digit; + + /* Skip white space */ + for (digit = *expr; digit && *digit && isspace (*digit); ++digit); + + switch (*digit) + { + case '(': + + /* Scan for closing paren */ + for (++digit; **expr && **expr != ')'; ++(*expr)); + + /* Is there one? */ + if (!**expr) + return WRDE_SYNTAX; + + *(*expr)++ = 0; + + if (eval_expr(digit, result)) + return WRDE_SYNTAX; + + return 0; + + case '+': /* Positive value */ + ++digit; + break; + + case '-': /* Negative value */ + ++digit; + sgn = -1; + break; + + default: + if (!isdigit (*digit)) + return WRDE_SYNTAX; + } + + *result = 0; + for (; *digit && isdigit(*digit); ++digit) + *result = (*result * 10) + (*digit - '0'); + + *expr = digit; + *result *= sgn; + return 0; +} + +static int +eval_expr_multdiv (char **expr, int *result) +{ + int arg; + + /* Read a Value */ + if (eval_expr_val (expr, result)) + return WRDE_SYNTAX; + + while (**expr) + { + /* Skip white space */ + for (; *expr && **expr && isspace (**expr); ++(*expr)); + + if (**expr == '*') + { + (*expr)++; + if ((eval_expr_val (expr, &arg)) != 0) + return WRDE_SYNTAX; + + *result *= arg; + } + else if (**expr == '/') + { + (*expr)++; + if ((eval_expr_val (expr, &arg)) != 0) + return WRDE_SYNTAX; + + *result /= arg; + } + else break; + } + + return 0; +} + +static int +eval_expr (char *expr, int *result) +{ + int arg; + + /* Read a Multdiv */ + if ((eval_expr_multdiv (&expr, result)) != 0) + return WRDE_SYNTAX; + + while (*expr) + { + /* Skip white space */ + for (; expr && *expr && isspace (*expr); ++expr); + + if (*expr == '+') + { + expr++; + if ((eval_expr_multdiv (&expr, &arg)) != 0) + return WRDE_SYNTAX; + + *result += arg; + } + else if (*expr == '-') + { + expr++; + if ((eval_expr_multdiv (&expr, &arg)) != 0) + return WRDE_SYNTAX; + + *result -= arg; + } + else break; + } + + return 0; +} + +static int +parse_arith (char **word, size_t *word_length, const char *words, + size_t *offset, int flags, int bracket) +{ + /* We are poised just after "$((" or "$[" */ int error; + int paren_depth = 1; + size_t expr_length = 0; + char *expr = calloc (1, sizeof (char)); /* ??? */ + + if (expr == NULL) + return WRDE_NOSPACE; + + for (; words[*offset]; ++(*offset)) + { + switch (words[*offset]) + { + case '$': + error = parse_dollars (&expr, &expr_length, + words, offset, flags, NULL); + /* The NULL here is to tell parse_dollars not to + * split the fields. + */ + if (error) + { + free (expr); + return error; + } + break; + + case '`': + (*offset)++; + error = parse_backtick (&expr, &expr_length, + words, offset, flags, NULL); + /* The NULL here is to tell parse_backtick not to + * split the fields. + */ + if (error) + { + free (expr); + return error; + } + break; + + case '\\': + error = parse_qtd_backslash (&expr, &expr_length, words, offset); + if (error) + { + free (expr); + return error; + } + /* I think that a backslash within an + * arithmetic expansion is bound to + * cause an error sooner or later anyway though. + */ + break; + + case ')': + if (--paren_depth == 0) + { + char *result; + int numresult = 0; + + if (bracket || words[1 + *offset] != ')') + return WRDE_SYNTAX; + + ++(*offset); + + /* Go - evaluate. */ + if (*expr && + eval_expr (expr, &numresult) != 0) + return WRDE_SYNTAX; + + result = __alloca (100); + __snprintf (result, 100, "%d", numresult); + *word = w_addstr (*word, word_length, result); + free (expr); + return *word ? 0 : WRDE_NOSPACE; + } + expr = w_addchar (expr, &expr_length, words[*offset]); + if (expr == NULL) + return WRDE_NOSPACE; + + break; + + case ']': + if (bracket && paren_depth == 1) + { + char *result; + int numresult = 0; + + /* Go - evaluate. */ + if (*expr && eval_expr (expr, &numresult) != 0) + return WRDE_SYNTAX; + + result = __alloca (100); + __snprintf (result, 100, "%d", numresult); + *word = w_addstr (*word, word_length, result); + free (expr); + return *word ? 0 : WRDE_NOSPACE; + } + + free (expr); + return WRDE_SYNTAX; + + case '\n': + case ';': + case '{': + case '}': + free (expr); + return WRDE_BADCHAR; + + case '(': + ++paren_depth; + default: + expr = w_addchar (expr, &expr_length, words[*offset]); + if (expr == NULL) + return WRDE_NOSPACE; + } + } + + /* Premature end */ + free (expr); + return WRDE_SYNTAX; +} + +/* Function to execute a command and retrieve the results */ +/* pwordexp contains NULL if field-splitting is forbidden */ +static int +exec_comm (char *comm, char **word, size_t *word_length, int flags, + wordexp_t *pwordexp) +{ + int fildes[2]; + int bufsize = 128; + int buflen; + int state = 0; + int i; + char *sh, *buffer; pid_t pid; - int d[2]; - int status; + /* 'state' is: + * 0 until first non-(whitespace-ifs) + * 1 after a non-ifs + * 2 after non-(whitespace-ifs) + */ - FILE *f; - size_t wordc, start, buflen; - char *buf; + /* Don't fork() unless necessary */ + if (!comm || !*comm) + return 0; - /* Create the pipe through which we will communicate to the shell. */ - if (pipe (d) < 0) - return -1; + if (pipe (fildes)) + /* Bad */ + return WRDE_NOSPACE; - pid = fork (); - if (pid < 0) - return -1; + if ((pid = fork ()) < 0) + { + /* Bad */ + return WRDE_NOSPACE; + } if (pid == 0) { - /* Child. Run the shell. */ + /* Child */ + /* Redirect input and output */ + dup2 (fildes[1], 1); - const char *argv[5]; + /* Close stderr if we have to */ + if ((flags & WRDE_SHOWERR) == 0) + close (2); - close (d[STDIN_FILENO]); - dup2 (d[STDOUT_FILENO], STDOUT_FILENO); - if (!(flags & WRDE_SHOWERR)) - close (STDERR_FILENO); + execl (_PATH_BSHELL, _PATH_BSHELL, "-c", comm, NULL); + /* Bad */ + exit (1); + } - 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; + /* Parent */ + + close (fildes[1]); + buffer = __alloca (bufsize); - execv (SHELL_PATH, argv); - _exit (WRDE_NOSPACE); + if (!pwordexp) + { /* Quoted - no field splitting */ + + while (1) + { + if ((buflen = read (fildes[0], buffer, bufsize)) < 1) + { + if (waitpid (pid, NULL, WNOHANG) == 0) + continue; + if ((buflen = read (fildes[0], buffer, bufsize)) < 1) + break; + } + + for (i = 0; i < buflen; ++i) + { + *word = w_addchar (*word, word_length, buffer[i]); + if (*word == NULL) + { + close (fildes[0]); + return WRDE_NOSPACE; + } + } + } + + close (fildes[0]); + return 0; } - /* Parent. */ + /* Not quoted - split fields. + * NB. This isn't done properly yet. + */ + while (1) + { + if ((buflen = read (fildes[0], buffer, bufsize)) < 1) + { + if (waitpid (pid, NULL, WNOHANG) == 0) + continue; + if ((read (fildes[0], buffer, bufsize)) < 1) + break; + } - buf = NULL; - error = WRDE_NOSPACE; + for (i = 0; i < buflen; ++i) + { + /* What if these aren't field separators? FIX */ + if ((buffer[i] == ' ') || (buffer[i] == '\t') || (buffer[i] == '\n')) + { + if (state != 0) + state = 2; + continue; + } - close (d[STDOUT_FILENO]); - f = fdopen (d[STDIN_FILENO]); - if (f == NULL) - goto lose; + if (state == 2) + { + /* End of word */ + if (w_addword (pwordexp, *word) == WRDE_NOSPACE) + { + close (fildes[0]); + return WRDE_NOSPACE; + } - /* 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; + *word = NULL; + *word_length = 0; + } - /* 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; + state = 1; + *word = w_addchar (*word, word_length, buffer[i]); + if (*word == NULL) + { + close (fildes[0]); + return WRDE_NOSPACE; + } + } + } - if (WIFEXITED (status)) + close (fildes[0]); + return 0; +} + +static int +parse_comm (char **word, size_t *word_length, const char *words, + size_t *offset, int flags, wordexp_t *pwordexp) +{ + /* We are poised just after "$(" */ + int paren_depth = 1; + int error; + size_t comm_length = 0; + char *comm = calloc (1, sizeof (char)); /* ??? */ + + if (comm == NULL) + return WRDE_NOSPACE; + + for (; words[*offset]; ++(*offset)) { - if (WEXITSTATUS (status) != 0) + switch (words[*offset]) { - error = WEXITSTATUS (status); - goto lose; + case ')': + if (--paren_depth == 0) + { + /* Go -- give script to the shell */ + error = exec_comm (comm, word, word_length, flags, pwordexp); + free (comm); + return error; + } + + /* This is just part of the script */ + comm = w_addchar (comm, &comm_length, words[*offset]); + if (comm == NULL) + return WRDE_NOSPACE; + + break; + + case '(': + paren_depth++; + default: + comm = w_addchar (comm, &comm_length, words[*offset]); + if (comm == NULL) + return WRDE_NOSPACE; + + break; } } - else - goto lose; - /* Pack the structure. */ + /* Premature end */ + free (comm); + return WRDE_SYNTAX; +} - 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 ((void *) pwordexp->we_wordv, - wordc * sizeof (char *)); +static int +parse_param (char **word, size_t *word_length, const char *words, + size_t *offset, int flags, wordexp_t *pwordexp) +{ + /* We are poised just after "$" */ + size_t start = *offset; + size_t env_length = 0; + size_t pat_length = 0; + char *env = calloc (1, sizeof (char)); /* ??? */ + char *pattern = calloc (1, sizeof (char)); /* ??? */ + char *value; + char action = 0; + int prefix = 0; + int suffix = 0; + int colon_seen = 0; + int depth = 0; + int error; + + if ((env == NULL) || (pattern == NULL)) + return WRDE_NOSPACE; + + for (; words[*offset]; ++(*offset)) + { + switch (words[*offset]) + { + case '{': + if (action || prefix || suffix) + { + ++depth; + pattern = w_addchar (pattern, &pat_length, words[*offset]); + if (pattern == NULL) + goto no_space; + + break; + } + + if (*offset == start) + break; + /* Otherwise evaluate */ + /* (and re-parse this character) */ + --(*offset); + goto envsubst; + + case '}': + if (words[start] != '{') + { + --(*offset); + } + + if (action || prefix || suffix) + { + if (--depth) + { + pattern = w_addchar (pattern, &pat_length, words[*offset]); + if (pattern == NULL) + goto no_space; + + break; + } + } + + /* Evaluate */ + goto envsubst; + + case '#': + case '%': + if (words[start] == '{') + { + /* At the start? (ie. 'string length') */ + if (*offset == start + 1) + break; + + /* Separating variable name from prefix pattern? */ + if (words[*offset] == '#') + { + if ((prefix < 2) && (!suffix)) + { + ++prefix; + break; + } + } + else + { + if ((suffix < 2) && (!prefix)) + { + ++suffix; + break; + } + } + + /* Must be part of prefix/suffix pattern. */ + pattern = w_addchar (pattern, &pat_length, words[*offset]); + if (pattern == NULL) + goto no_space; + + break; + } + /* Otherwise evaluate */ + /* (and re-parse this character) */ + --(*offset); + goto envsubst; + + case ':': + if (!*env) + { + free (env); + free (pattern); + return WRDE_SYNTAX; + } + + if (action || prefix || suffix) + { + pattern = w_addchar (pattern, &pat_length, words[*offset]); + if (pattern == NULL) + goto no_space; + + break; + } + + if ((words[1 + *offset] == '-') || (words[1 + *offset] == '=') || + (words[1 + *offset] == '?') || (words[1 + *offset] == '+')) + { + colon_seen = 1; + break; + } + + free (env); + free (pattern); + return WRDE_SYNTAX; + + case '-': + case '=': + case '?': + case '+': + if (!*env) + { + free (env); + free (pattern); + return WRDE_SYNTAX; + } + + if (action || prefix || suffix) + { + pattern = w_addchar (pattern, &pat_length, words[*offset]); + if (pattern == NULL) + { + free (env); + return WRDE_NOSPACE; + } + + break; + } + + action = words[*offset]; + break; + + case '\\': + if (action || prefix || suffix) + { + error = parse_qtd_backslash (word, word_length, words, offset); + if (error == 0) + break; + } + else + { + error = WRDE_SYNTAX; + } + + free (env); + free (pattern); + return error; + + default: + if (action || prefix || suffix) + { + pattern = w_addchar (pattern, &pat_length, words[*offset]); + if (pattern == NULL) + goto no_space; + + break; + } + + if ((words[start] == '{') || isalpha (words[*offset])) + { + env = w_addchar (env, &env_length, words[*offset]); + if (env == NULL) + goto no_space; + + break; + } + + --(*offset); + goto envsubst; + } + } + + /* End of input string */ + --(*offset); + +envsubst: + if (words[start] == '{' && words[*offset] != '}') + { + free (env); + free (pattern); + return WRDE_SYNTAX; + } + + if (!env || !*env) + { + *offset = start - 1; + *word = w_addchar (*word, word_length, '$'); + free (env); + free (pattern); + return *word ? 0 : WRDE_NOSPACE; + } + + value = getenv (env); + + if (action || prefix || suffix) + { + switch (action) + { + case 0: + /* For the time being, pattern is ignored */ + printf ("Pattern: %s\nPrefix: %d\nSuffix: %d\n", pattern, prefix, suffix); + break; + + case '?': + if (value && *value) + break; + + if (!colon_seen && value) + { + /* Substitute NULL */ + free (env); + free (pattern); + return 0; + } + + /* Error - exit */ + fprintf (stderr, "%s: ", env); + + if (*pattern) + { + /* Expand 'pattern' and write it to stderr */ + wordexp_t we; + + error = wordexp (pattern, &we, flags); + + if (error == 0) + { + int i; + + for (i = 0; i < we.we_wordc; ++i) + { + fprintf (stderr, "%s%s", i ? " " : "", we.we_wordv[i]); + } + + fprintf (stderr, "\n"); + error = WRDE_BADVAL; + } + + wordfree (&we); + free (env); + free (pattern); + return error; + } + + fprintf (stderr, "parameter null or not set\n"); + free (env); + free (pattern); + return WRDE_BADVAL; + + default: + printf ("warning: parameter substitution does not yet support \"%s%c\"\n", colon_seen?":":"", action); + } + } + + free (env); + free (pattern); + + if (!value) + { + /* Variable not defined */ + if (flags & WRDE_UNDEF) + return WRDE_SYNTAX; + + return 0; + } + + if (!pwordexp) + /* Quoted - no field split */ + *word = w_addstr (*word, word_length, value); else - wordv = (char **) malloc (wordc * sizeof (char *)); - if (wordv == NULL) - goto lose; + /* Should field-split here - FIX */ + *word = w_addstr (*word, word_length, value); - if (flags & WRDE_DOOFFS) - for (i = 0; i < pwordexp->we_offs; ++i) - wordv[i] = NULL; + return *word ? 0 : WRDE_NOSPACE; + +no_space: + if (env) + free (env); + + if (pattern) + free (pattern); - for (i = start; i < wordc; ++i) + return WRDE_NOSPACE; +} + +static int +parse_dollars (char **word, size_t *word_length, const char *words, + size_t *offset, int flags, wordexp_t *pwordexp) +{ + /* We are poised _at_ "$" */ + switch (words[1 + *offset]) { - pwordexp->we_wordv[i] = buf; - buf = strchr (buf, '\0') + 1; + case '"': + case '\'': + case 0: + *word = w_addchar (*word, word_length, '$'); + return *word ? 0 : WRDE_NOSPACE; + + case '(': + if (words[2 + *offset] == '(') + { + (*offset) += 3; + /* Call parse_arith -- 0 is for "no brackets" */ + return parse_arith (word, word_length, words, offset, flags, 0); + } + + if (flags & WRDE_NOCMD) + return WRDE_CMDSUB; + + (*offset) += 2; + return parse_comm (word, word_length, words, offset, flags, pwordexp); + + case '[': + (*offset) += 2; + /* Call parse_arith -- 1 is for "brackets" */ + return parse_arith (word, word_length, words, offset, flags, 1); + + case '{': + default: + ++(*offset); /* parse_param needs to know if "{" is there */ + return parse_param (word, word_length, words, offset, flags, pwordexp); } - wordv[i] = NULL; +} - if (flags & WRDE_REUSE) +static int +parse_backtick (char **word, size_t *word_length, const char *words, + size_t *offset, int flags, wordexp_t *pwordexp) +{ + /* We are poised just after "`" */ + int error; + size_t comm_length = 0; + char *comm = calloc (1, sizeof (char)); /* ??? */ + int squoting = 0; + + for (; words[*offset]; ++(*offset)) { - free (pwordexp->we_wordv[0]); - if (!(flags & WRDE_APPEND)) - free (pwordexp->we_wordv); + switch (words[*offset]) + { + case '`': + /* Go -- give the script to the shell */ + error = exec_comm (comm, word, word_length, flags, pwordexp); + free (comm); + return error; + + case '\\': + if (squoting) + { + error = parse_qtd_backslash (&comm, &comm_length, words, offset); + + if (error) + { + free (comm); + return error; + } + + break; + } + + ++(*offset); + error = parse_backslash (&comm, &comm_length, words, offset); + + if (error) + { + free (comm); + return error; + } + + break; + + case '\'': + squoting = 1 - squoting; + default: + comm = w_addchar (comm, &comm_length, words[*offset]); + if (comm == NULL) + return WRDE_NOSPACE; + } } - pwordexp->we_wordc = wordc; - pwordexp->we_wordv = wordv; + /* Premature end */ + free (comm); + return WRDE_SYNTAX; +} - return 0; +static int +parse_dquote (char **word, size_t *word_length, const char *words, + size_t *offset, int flags) +{ + /* We are poised just after a double-quote */ + int error; + + for (; words[*offset]; ++(*offset)) + { + switch (words[*offset]) + { + case '"': + return 0; + + case '$': + error = parse_dollars (word, word_length, words, offset, flags, + NULL); + /* The NULL here is to tell parse_dollars not to + * split the fields. + */ + if (error) + return error; - lose: - { - int save; - save = errno; - (void) kill (pid, SIGKILL); - free (buf); - (void) waitpid (pid, (int *) NULL, 0); - errno = save; - return error; - } + break; + + case '`': + if (flags & WRDE_NOCMD) + { + return WRDE_CMDSUB; + } + + ++(*offset); + error = parse_backtick (word, word_length, words, offset, flags, + NULL); + /* The NULL here is to tell parse_backtick not to + * split the fields. + */ + if (error) + return error; + + break; + + case '\\': + error = parse_qtd_backslash (word, word_length, words, offset); + + if (error) + return error; + + break; + + default: + *word = w_addchar (*word, word_length, words[*offset]); + if (*word == NULL) + return WRDE_NOSPACE; + } + } + + /* Unterminated string */ + return WRDE_SYNTAX; } +/* + * wordfree() is to be called after pwordexp is finished with. + */ void -DEFUN(wordexp, (pwordexp), wordexp_t *pwordexp) +wordfree (wordexp_t *pwordexp) { - /* All the other elts point into the first. */ - free (pwordexp->we_wordv[0]); - free (pwordexp->we_wordv); + + /* wordexp can set pwordexp to NULL */ + if (pwordexp && pwordexp->we_wordv) + { + char **wordv = pwordexp->we_wordv; + + for (wordv += pwordexp->we_offs; *wordv; ++wordv) + free (*wordv); + + free (pwordexp->we_wordv); + pwordexp->we_wordv = NULL; + } +} + +/* + * wordexp() + */ + +int +wordexp (const char *words, wordexp_t *pwordexp, int flags) +{ + size_t wordv_offset; + size_t words_offset; + size_t word_length = 0; + int error; + char *word = NULL; + char *ifs; + char ifs_white[4]; + char **old_wordv = pwordexp->we_wordv; + size_t old_wordc = pwordexp->we_wordc; + + if (flags & WRDE_REUSE) + /* Minimal implementation of WRDE_REUSE for now */ + wordfree (pwordexp); + + if (flags & WRDE_DOOFFS) + { + pwordexp->we_wordv = calloc (1 + pwordexp->we_offs, sizeof (char *)); + if (pwordexp->we_wordv == NULL) + return WRDE_NOSPACE; + } + else + { + pwordexp->we_wordv = calloc (1, sizeof (char *)); + if (pwordexp->we_wordv == NULL) + return WRDE_NOSPACE; + + pwordexp->we_offs = 0; + } + + if ((flags & WRDE_APPEND) == 0) + pwordexp->we_wordc = 0; + + wordv_offset = pwordexp->we_offs + pwordexp->we_wordc; + + /* Find out what the field separators are. + * There are two types: whitespace and non-whitespace. + */ + ifs = getenv ("IFS"); + + if (!ifs) + ifs = strcpy (ifs_white, " \t\n"); + else + { + char *ifsch = ifs; + char *whch = ifs_white; + + while (*ifsch != '\0') + if ((*ifsch == ' ') || (*ifsch == '\t') || (*ifsch == '\n')) + { + /* White space IFS. Se first whether it is already in our + collection. */ + char *runp = ifs_white; + + while (runp < whch && *runp != '\0') + ++runp; + + if (runp == whch) + *whch++ = *ifsch; + } + *whch = '\0'; + } + + for (words_offset = 0 ; words[words_offset] ; ++words_offset) + switch (words[words_offset]) + { + case '\n': + case '|': + case '&': + case ';': + case '<': + case '>': + case '(': + case ')': + case '}': + /* Fail */ + wordfree (pwordexp); + pwordexp->we_wordc = 0; + pwordexp->we_wordv = old_wordv; + return WRDE_BADCHAR; + + case '\\': + error = parse_backslash (&word, &word_length, words, &words_offset); + + if (error) + goto do_error; + + break; + + case '$': + error = parse_dollars (&word, &word_length, words, &words_offset, + flags, pwordexp); + + if (error) + goto do_error; + + break; + + case '`': + if (flags & WRDE_NOCMD) + return WRDE_CMDSUB; + + ++words_offset; + error = parse_backtick (&word, &word_length, words, &words_offset, + flags, pwordexp); + + if (error) + goto do_error; + + break; + + case '"': + ++words_offset; + error = parse_dquote (&word, &word_length, words, &words_offset, + flags); + + if (error) + goto do_error; + + break; + + case '\'': + ++words_offset; + error = parse_squote (&word, &word_length, words, &words_offset); + + if (error) + goto do_error; + + break; + + case '~': + error = parse_tilde (&word, &word_length, words, &words_offset, + pwordexp->we_wordc); + + if (error) + goto do_error; + + break; + + case '*': + case '{': + error = parse_glob (&word, &word_length, words, &words_offset, flags, + pwordexp, ifs); + + if (error) + goto do_error; + + break; + + default: + /* Is it a field separator? */ + if (strchr (ifs, words[words_offset]) == NULL) + { + /* "Ordinary" character -- add it to word */ + + word = w_addchar (word, &word_length, words[words_offset]); + if (word == NULL) + { + error = WRDE_NOSPACE; + goto do_error; + } + + break; + } + + /* Field separator */ + if (strchr (ifs_white, words[words_offset])) + { + /* It's a whitespace IFS char. Ignore it at the beginning + of a line and ignore multiple instances. */ + if (!word || !*word) + break; + + if (w_addword (pwordexp, word) == WRDE_NOSPACE) + { + error = WRDE_NOSPACE; + goto do_error; + } + + word = NULL; + word_length = 0; + break; + } + + /* It's a non-whitespace IFS char */ + if (!word) + { + word = calloc (1, sizeof (char)); /* ??? */ + if (word == NULL) + { + error = WRDE_NOSPACE; + goto do_error; + } + } + + if (w_addword (pwordexp, word) == WRDE_NOSPACE) + { + error = WRDE_NOSPACE; + goto do_error; + } + + word = NULL; + word_length = 0; + } + + /* End of string */ + + /* There was a field separator at the end */ + if (!word || !*word) + return 0; + + /* There was no field separator at the end */ + return w_addword (pwordexp, word); + +do_error: + /* Error: + free memory used, set we_wordc and wd_wordv back to what they were. + */ + if (word != NULL) + free (word); + + wordfree (pwordexp); + pwordexp->we_wordv = old_wordv; + pwordexp->we_wordc = old_wordc; + return error; } |