diff options
| -rw-r--r-- | lib/include/util.h | 12 | ||||
| -rw-r--r-- | lib/src/rdline.c | 47 |
2 files changed, 58 insertions, 1 deletions
diff --git a/lib/include/util.h b/lib/include/util.h index 9ba9ffb..6943567 100644 --- a/lib/include/util.h +++ b/lib/include/util.h @@ -43,6 +43,18 @@ typedef struct { cleared if end-of-file is reached. The line must be deallocated with free(). + + The following transformations are applied: + - Space characters are replaced with regular white space characters. + - Sequences of space characters are truncated to a single space. + - A '#' sign is interpreted as the start of a comment and removed, + together with everything that follows. + - Padding spaces are removed from the line. + - If a '"' is encounterd, the above rules are disabled, until a + after the matching '"' is read. A '"' can be escaped by preceeding + it with a backslash. + - If a second, coresponding '"' is not found, processing fails with + errno set to EILSEQ. */ char *rdline(int fd); diff --git a/lib/src/rdline.c b/lib/src/rdline.c index 1b91008..4e72a25 100644 --- a/lib/src/rdline.c +++ b/lib/src/rdline.c @@ -22,11 +22,18 @@ #include "util.h" +enum { + STATE_INITIAL = 0, + STATE_STRING = 1, + STATE_STRING_ESC = 2, + STATE_COMMENT = 3, +}; + char *rdline(int fd) { size_t i = 0, bufsiz = 0, newsz; + int ret, state = STATE_INITIAL; char c, *new, *buffer = NULL; - int ret; for (;;) { switch (read(fd, &c, 1)) { @@ -47,6 +54,39 @@ char *rdline(int fd) goto fail; } + switch (state) { + case STATE_STRING: + if (c == '\\') + state = STATE_STRING_ESC; + if (c == '"') + state = STATE_INITIAL; + break; + case STATE_STRING_ESC: + state = STATE_STRING; + break; + case STATE_COMMENT: + if (c != '\0') + continue; + break; + default: + if (isspace(c)) + c = ' '; + if (c == ' ' && (i == 0 || buffer[i - 1] == ' ')) + continue; + if (c == '#') { + state = STATE_COMMENT; + continue; + } + if (c == '"') + state = STATE_STRING; + break; + } + + if (c == '\0') { + while (i > 0 && buffer[i - 1] == ' ') + --i; + } + if (i == bufsiz) { newsz = bufsiz ? bufsiz * 2 : 16; new = realloc(buffer, newsz); @@ -62,6 +102,11 @@ char *rdline(int fd) if (c == '\0') break; } + + if (state == STATE_STRING || state == STATE_STRING_ESC) { + errno = EILSEQ; + goto fail; + } return buffer; fail: ret = errno; |