X-Git-Url: https://git.ozlabs.org/?a=blobdiff_plain;f=discover%2Fgrub2%2Fscript.c;h=9cc0cfba4b4334a757e8056016ffe56f2db948e3;hb=2ea5eb23b027519372dd20fbe8f958c06ac2aa6c;hp=fce4f0afde487f8fc623ccc2ab519bf2d4ecee0e;hpb=5c6c8ea8ca66fe70563143cb226852a10b1a98fb;p=petitboot diff --git a/discover/grub2/script.c b/discover/grub2/script.c index fce4f0a..9cc0cfb 100644 --- a/discover/grub2/script.c +++ b/discover/grub2/script.c @@ -55,16 +55,87 @@ static bool expand_var(struct grub2_script *script, struct grub2_word *word) { const char *val; - val = script_env_get(script, word->var.name); + val = script_env_get(script, word->name); if (!val) val = ""; - word->type = GRUB2_WORD_TEXT; word->text = talloc_strdup(script, val); return true; } +static bool is_delim(char c) +{ + return c == ' ' || c == '\t'; +} + +/* For non-double-quoted variable expansions, we may need to split the + * variable's value into multiple argv items. + * + * This function sets the word->text to the initial set of non-delimiter chars + * in the expanded var value. We then skip any delimiter chars, and (if + * required), create the new argv item with the remaining text, and + * add it to the argv list, after top_word. + */ +static void process_split(struct grub2_script *script, + struct grub2_word *top_word, + struct grub2_word *word) +{ + int i, len, delim_start = -1, delim_end = -1; + struct grub2_word *new_word; + char *remainder; + + len = strlen(word->text); + + /* Scan our string for the start of a delim (delim_start), and the + * start of any new text (delim_end). */ + for (i = 0; i < len; i++) { + if (is_delim(word->text[i])) { + if (delim_start == -1) + delim_start = i; + } else if (delim_start != -1) { + delim_end = i; + break; + } + } + + /* No delim? nothing to do. The process_expansions loop will + * append this word's text to the top word, if necessary + */ + if (delim_start == -1) + return; + + /* Set this word's text value to the text before the delimiter. + * this will get appended to the top word + */ + word->text[delim_start] = '\0'; + + /* No trailing text? If there are no following word tokens, we're done. + * Otherwise, we need to start a new argv item with those tokens */ + if (delim_end == -1) { + if (!word->next) + return; + remainder = ""; + } else { + remainder = word->text + delim_end; + } + + new_word = talloc(script, struct grub2_word); + new_word->type = GRUB2_WORD_TEXT; + /* if there's no trailing text, we know we don't need to re-split */ + new_word->split = delim_end != -1; + new_word->next = word->next; + new_word->last = NULL; + new_word->text = talloc_strdup(new_word, remainder); + + /* stitch it into the argv list before this word */ + list_insert_after(&top_word->argv_list, + &new_word->argv_list); + + /* terminate this word */ + word->next = NULL; +} + /* iterate through the words in an argv_list, looking for GRUB2_WORD_VAR * expansions. * @@ -82,22 +153,36 @@ static void process_expansions(struct grub2_script *script, list_for_each_entry(&argv->words, top_word, argv_list) { argv->argc++; - /* expand vars and squash the list of words into the top struct. - * todo: splitting - */ + /* expand vars and squash the list of words into the head + * of the argv word list */ for (word = top_word; word; word = word->next) { - if (word->type == GRUB2_WORD_VAR) + + /* if it's a variable, perform the substitution */ + if (word->type == GRUB2_WORD_VAR) { expand_var(script, word); + word->type = GRUB2_WORD_TEXT; + } + + /* split; this will potentially insert argv + * entries after top_word. */ + if (word->split) + process_split(script, top_word, word); + + /* accumulate word text into the top word, so + * we end up with a shallow tree of argv data */ + /* todo: don't do this in process_split */ + if (word != top_word) { + top_word->text = talloc_asprintf_append( + top_word->text, + "%s", word->text); + } - if (word == top_word) - continue; - top_word->text = talloc_asprintf_append(top_word->text, - "%s", word->text); } top_word->next = NULL; } + /* convert the list to an argv array, to pass to the function */ argv->argv = talloc_array(script, char *, argv->argc); i = 0; @@ -105,7 +190,7 @@ static void process_expansions(struct grub2_script *script, argv->argv[i++] = word->text; } -int statements_execute(struct grub2_script *script, +static int statements_execute(struct grub2_script *script, struct grub2_statements *stmts) { struct grub2_statement *stmt;