+#include <glob.h>
+#include <string.h>
+#include <stdlib.h>
+
+#include "uci.h"
+#include "uci_internal.h"
+
+#define LINEBUF 32
+#define LINEBUF_MAX 4096
+
+/*
+ * Fetch a new line from the input stream and resize buffer if necessary
+ */
+__private void uci_getln(struct uci_context *ctx, int offset)
+{
+ struct uci_parse_context *pctx = ctx->pctx;
+ char *p;
+ int ofs;
+
+ if (pctx->buf == NULL) {
+ pctx->buf = uci_malloc(ctx, LINEBUF);
+ pctx->bufsz = LINEBUF;
+ }
+
+ ofs = offset;
+ do {
+ p = &pctx->buf[ofs];
+ p[ofs] = 0;
+
+ p = fgets(p, pctx->bufsz - ofs, pctx->file);
+ if (!p || !*p)
+ return;
+
+ ofs += strlen(p);
+ if (pctx->buf[ofs - 1] == '\n') {
+ pctx->line++;
+ pctx->buf[ofs - 1] = 0;
+ return;
+ }
+
+ if (pctx->bufsz > LINEBUF_MAX/2)
+ uci_parse_error(ctx, p, "line too long");
+
+ pctx->bufsz *= 2;
+ pctx->buf = uci_realloc(ctx, pctx->buf, pctx->bufsz);
+ } while (1);
+}
+
+
+/*
+ * parse a character escaped by '\'
+ * returns true if the escaped character is to be parsed
+ * returns false if the escaped character is to be ignored
+ */
+static inline bool parse_backslash(struct uci_context *ctx, char **str)
+{
+ /* skip backslash */
+ *str += 1;
+
+ /* undecoded backslash at the end of line, fetch the next line */
+ if (!**str) {
+ *str += 1;
+ uci_getln(ctx, *str - ctx->pctx->buf);
+ return false;
+ }
+
+ /* FIXME: decode escaped char, necessary? */
+ return true;
+}
+
+/*
+ * move the string pointer forward until a non-whitespace character or
+ * EOL is reached
+ */
+static void skip_whitespace(struct uci_context *ctx, char **str)
+{
+restart:
+ while (**str && isspace(**str))
+ *str += 1;
+
+ if (**str == '\\') {
+ if (!parse_backslash(ctx, str))
+ goto restart;
+ }
+}
+
+static inline void addc(char **dest, char **src)
+{
+ **dest = **src;
+ *dest += 1;
+ *src += 1;
+}
+
+/*
+ * parse a double quoted string argument from the command line
+ */
+static void parse_double_quote(struct uci_context *ctx, char **str, char **target)
+{
+ char c;
+
+ /* skip quote character */
+ *str += 1;
+
+ while ((c = **str)) {
+ switch(c) {
+ case '"':
+ **target = 0;
+ *str += 1;
+ return;
+ case '\\':
+ if (!parse_backslash(ctx, str))
+ continue;
+ /* fall through */
+ default:
+ addc(target, str);
+ break;
+ }
+ }
+ uci_parse_error(ctx, *str, "unterminated \"");
+}
+
+/*
+ * parse a single quoted string argument from the command line
+ */
+static void parse_single_quote(struct uci_context *ctx, char **str, char **target)
+{
+ char c;
+ /* skip quote character */
+ *str += 1;
+
+ while ((c = **str)) {
+ switch(c) {
+ case '\'':
+ **target = 0;
+ *str += 1;
+ return;
+ default:
+ addc(target, str);
+ }
+ }
+ uci_parse_error(ctx, *str, "unterminated '");
+}
+
+/*
+ * parse a string from the command line and detect the quoting style
+ */
+static void parse_str(struct uci_context *ctx, char **str, char **target)
+{
+ bool next = true;
+ do {
+ switch(**str) {
+ case '\'':
+ parse_single_quote(ctx, str, target);
+ break;
+ case '"':
+ parse_double_quote(ctx, str, target);
+ break;
+ case '#':
+ **str = 0;
+ /* fall through */
+ case 0:
+ goto done;
+ case ';':
+ next = false;
+ goto done;
+ case '\\':
+ if (!parse_backslash(ctx, str))
+ continue;
+ /* fall through */
+ default:
+ addc(target, str);
+ break;
+ }
+ } while (**str && !isspace(**str));
+done:
+
+ /*
+ * if the string was unquoted and we've stopped at a whitespace
+ * character, skip to the next one, because the whitespace will
+ * be overwritten by a null byte here
+ */
+ if (**str && next)
+ *str += 1;
+
+ /* terminate the parsed string */
+ **target = 0;
+}
+
+/*
+ * extract the next argument from the command line
+ */
+static char *next_arg(struct uci_context *ctx, char **str, bool required, bool name)
+{
+ char *val;
+ char *ptr;
+
+ val = ptr = *str;
+ skip_whitespace(ctx, str);
+ if(*str[0] == ';') {
+ *str[0] = 0;
+ *str += 1;
+ } else {
+ parse_str(ctx, str, &ptr);
+ }
+ if (!*val) {
+ if (required)
+ uci_parse_error(ctx, *str, "insufficient arguments");
+ goto done;
+ }
+
+ if (name && !uci_validate_name(val))
+ uci_parse_error(ctx, val, "invalid character in field");
+
+done:
+ return val;
+}
+
+int uci_parse_argument(struct uci_context *ctx, FILE *stream, char **str, char **result)
+{
+ UCI_HANDLE_ERR(ctx);
+ UCI_ASSERT(ctx, str != NULL);
+ UCI_ASSERT(ctx, result != NULL);
+
+ if (ctx->pctx && (ctx->pctx->file != stream))
+ uci_cleanup(ctx);
+
+ if (!ctx->pctx)
+ uci_alloc_parse_context(ctx);
+
+ ctx->pctx->file = stream;
+
+ if (!*str) {
+ uci_getln(ctx, 0);
+ *str = ctx->pctx->buf;
+ }
+
+ *result = next_arg(ctx, str, false, false);
+
+ return 0;
+}
+
+static int
+uci_fill_ptr(struct uci_context *ctx, struct uci_ptr *ptr, struct uci_element *e)
+{
+ UCI_ASSERT(ctx, ptr != NULL);
+ UCI_ASSERT(ctx, e != NULL);
+
+ memset(ptr, 0, sizeof(struct uci_ptr));
+ switch(e->type) {
+ case UCI_TYPE_OPTION:
+ ptr->o = uci_to_option(e);
+ goto fill_option;
+ case UCI_TYPE_SECTION:
+ ptr->s = uci_to_section(e);
+ goto fill_section;
+ case UCI_TYPE_PACKAGE:
+ ptr->p = uci_to_package(e);
+ goto fill_package;
+ default:
+ UCI_THROW(ctx, UCI_ERR_INVAL);
+ }
+
+fill_option:
+ ptr->option = ptr->o->e.name;
+ ptr->s = ptr->o->section;
+fill_section:
+ ptr->section = ptr->s->e.name;
+ ptr->p = ptr->s->package;
+fill_package:
+ ptr->package = ptr->p->e.name;
+
+ ptr->flags |= UCI_LOOKUP_DONE;
+
+ return 0;
+}
+