*/
/*
- * This file contains wrappers to standard functions, which
- * throw exceptions upon failure.
+ * This file contains misc utility functions and wrappers to standard
+ * functions, which throw exceptions upon failure.
*/
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/file.h>
+#include <stdbool.h>
+#include <unistd.h>
+#include <ctype.h>
+#include <fcntl.h>
-static void *uci_malloc(struct uci_context *ctx, size_t size)
+#define LINEBUF 32
+#define LINEBUF_MAX 4096
+
+__plugin void *uci_malloc(struct uci_context *ctx, size_t size)
{
void *ptr;
return ptr;
}
-static void *uci_realloc(struct uci_context *ctx, void *ptr, size_t size)
+__plugin void *uci_realloc(struct uci_context *ctx, void *ptr, size_t size)
{
ptr = realloc(ptr, size);
if (!ptr)
return ptr;
}
-static char *uci_strdup(struct uci_context *ctx, const char *str)
+__plugin char *uci_strdup(struct uci_context *ctx, const char *str)
{
char *ptr;
return ptr;
}
+/* Based on an efficient hash function published by D. J. Bernstein */
+static unsigned int djbhash(unsigned int hash, char *str)
+{
+ int len = strlen(str);
+ int i;
+
+ /* initial value */
+ if (hash == ~0)
+ hash = 5381;
+
+ for(i = 0; i < len; i++) {
+ hash = ((hash << 5) + hash) + str[i];
+ }
+ return (hash & 0x7FFFFFFF);
+}
+
+/*
+ * validate strings for names and types, reject special characters
+ * for names, only alphanum and _ is allowed (shell compatibility)
+ * for types, we allow more characters
+ */
+__plugin bool uci_validate_str(const char *str, bool name)
+{
+ if (!*str)
+ return false;
+
+ while (*str) {
+ char c = *str;
+ if (!isalnum(c) && c != '_') {
+ if (name || (c < 33) || (c > 126))
+ return false;
+ }
+ str++;
+ }
+ return true;
+}
+
+static inline bool uci_validate_name(const char *str)
+{
+ return uci_validate_str(str, true);
+}
+
+static void uci_alloc_parse_context(struct uci_context *ctx)
+{
+ ctx->pctx = (struct uci_parse_context *) uci_malloc(ctx, sizeof(struct uci_parse_context));
+}
+
+int uci_parse_tuple(struct uci_context *ctx, char *str, char **package, char **section, char **option, char **value)
+{
+ char *last = NULL;
+
+ UCI_HANDLE_ERR(ctx);
+ UCI_ASSERT(ctx, str && package && section && option);
+
+ last = strchr(str, '=');
+ if (last) {
+ *last = 0;
+ last++;
+ }
+
+ *package = strsep(&str, ".");
+ if (!*package || !uci_validate_name(*package))
+ goto error;
+
+ *section = strsep(&str, ".");
+ if (!*section)
+ goto lastval;
+
+ *option = strsep(&str, ".");
+ if (!*option)
+ goto lastval;
+
+lastval:
+ if (last) {
+ if (!value)
+ goto error;
+
+ if (!*last)
+ goto error;
+ *value = last;
+ }
+
+ if (*section && *section[0] && !uci_validate_name(*section))
+ goto error;
+ if (*option && !uci_validate_name(*option))
+ goto error;
+
+ goto done;
+
+error:
+ UCI_THROW(ctx, UCI_ERR_PARSE);
+
+done:
+ return 0;
+}
+
+
+static void uci_parse_error(struct uci_context *ctx, char *pos, char *reason)
+{
+ struct uci_parse_context *pctx = ctx->pctx;
+
+ pctx->reason = reason;
+ pctx->byte = pos - pctx->buf;
+ UCI_THROW(ctx, UCI_ERR_PARSE);
+}
+
+
+/*
+ * Fetch a new line from the input stream and resize buffer if necessary
+ */
+static 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) {
+ if (ctx->pctx->file != stream) {
+ uci_cleanup(ctx);
+ }
+ } else {
+ 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;
+}
+
+
+/*
+ * open a stream and go to the right position
+ *
+ * note: when opening for write and seeking to the beginning of
+ * the stream, truncate the file
+ */
+static FILE *uci_open_stream(struct uci_context *ctx, const char *filename, int pos, bool write, bool create)
+{
+ struct stat statbuf;
+ FILE *file = NULL;
+ int fd, ret;
+ int mode = (write ? O_RDWR : O_RDONLY);
+
+ if (create)
+ mode |= O_CREAT;
+
+ if (!write && ((stat(filename, &statbuf) < 0) ||
+ ((statbuf.st_mode & S_IFMT) != S_IFREG))) {
+ UCI_THROW(ctx, UCI_ERR_NOTFOUND);
+ }
+
+ fd = open(filename, mode, UCI_FILEMODE);
+ if (fd < 0)
+ goto error;
+
+ if (flock(fd, (write ? LOCK_EX : LOCK_SH)) < 0)
+ goto error;
+
+ ret = lseek(fd, 0, pos);
+
+ if (ret < 0)
+ goto error;
+
+ file = fdopen(fd, (write ? "w+" : "r"));
+ if (file)
+ goto done;
+
+error:
+ UCI_THROW(ctx, UCI_ERR_IO);
+done:
+ return file;
+}
+
+static void uci_close_stream(FILE *stream)
+{
+ int fd;
+
+ if (!stream)
+ return;
+
+ fd = fileno(stream);
+ flock(fd, LOCK_UN);
+ fclose(stream);
+}
+
projects / project / uci.git / blobdiff