Changeset 08053f7 in mainline

Timestamp:

2011-07-06T23:33:02Z (13 years ago)

Author:

Petr Koupy <petr.koupy@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

324d46b

Parents:

d9eaa43

Message:

Implementation of scanf (not tested yet, just compiles).

Location:

uspace/lib/posix

Files:

• Makefile (modified) (1 diff)
• stdio.c (modified) (8 diffs)
• stdio/scanf.c (added)

uspace/lib/posix/Makefile

@@ -47 +47 @@
         signal.c \
         stdio.c \
+        stdio/scanf.c \
         stdlib.c \
         stdlib/strtol.c \

uspace/lib/posix/stdio.c

@@ -49 +49 @@
 #include "libc/io/printf_core.h"
 #include "libc/str.h"
+#include "libc/malloc.h"
 
 
@@ -92 +93 @@
  * @param c Byte to be pushed back.
  * @param stream Stream to where the byte shall be pushed.
- * @return Provided byte on succes or EOF if not possible.
+ * @return Provided byte on success or EOF if not possible.
  */
 int posix_ungetc(int c, FILE *stream)
@@ -128 +129 @@
 
 /**
- *
- * @param lineptr
- * @param n
- * @param delimiter
- * @param stream
- * @return
+ * Read a stream until the delimiter (or EOF) is encountered.
+ *
+ * @param lineptr Pointer to the output buffer in which there will be stored
+ *     nul-terminated string together with the delimiter (if encountered).
+ *     Will be resized if necessary.
+ * @param n Pointer to the size of the output buffer. Will be increased if
+ *     necessary.
+ * @param delimiter Delimiter on which to finish reading the stream.
+ * @param stream Input stream.
+ * @return Number of fetched characters (including delimiter if encountered)
+ *     or -1 on error (set in errno).
  */
 ssize_t posix_getdelim(char **restrict lineptr, size_t *restrict n,
     int delimiter, FILE *restrict stream)
 {
-        // TODO
-        not_implemented();
-}
-
-/**
- * 
- * @param lineptr
- * @param n
- * @param stream
- * @return
+        /* Check arguments for sanity. */
+        if (!lineptr || !n) {
+                errno = EINVAL;
+                return -1;
+        }
+
+        size_t alloc_step = 80; /* Buffer size gain during reallocation. */
+        char *pos = *lineptr; /* Next free byte of the output buffer. */
+        size_t cnt = 0; /* Number of fetched characters. */
+        int c = fgetc(stream); /* Current input character. Might be EOF. */
+
+        do {
+                /* Mask EOF as NUL to terminate string. */
+                if (c == EOF) {
+                        c = '\0';
+                }
+
+                /* Ensure there is still space left in the buffer. */
+                if (pos == *lineptr + *n) {
+                        *lineptr = realloc(*lineptr, *n + alloc_step);
+                        if (*lineptr) {
+                                pos = *lineptr + *n;
+                                *n += alloc_step;
+                        } else {
+                                errno = ENOMEM;
+                                return -1;
+                        }
+                }
+
+                /* Store the fetched character. */
+                *pos = c;
+
+                /* Fetch the next character according to the current character. */
+                if (c != '\0') {
+                        ++pos;
+                        ++cnt;
+                        if (c == delimiter) {
+                                /* Delimiter was just stored. Provide EOF as the next
+                                 * character - it will be masked as NUL and output string
+                                 * will be properly terminated. */
+                                c = EOF;
+                        } else {
+                                /* Neither delimiter nor EOF were encountered. Just fetch
+                                 * the next character from the stream. */
+                                c = fgetc(stream);
+                        }
+                }
+        } while (c != '\0');
+
+        if (errno == EOK && cnt > 0) {
+                return cnt;
+        } else {
+                /* Either some error occured or the stream was already at EOF. */
+                return -1;
+        }
+}
+
+/**
+ * Read a stream until the newline (or EOF) is encountered.
+ * 
+ * @param lineptr Pointer to the output buffer in which there will be stored
+ *     nul-terminated string together with the delimiter (if encountered).
+ *     Will be resized if necessary.
+ * @param n Pointer to the size of the output buffer. Will be increased if
+ *     necessary.
+ * @param stream Input stream.
+ * @return Number of fetched characters (including newline if encountered)
+ *     or -1 on error (set in errno).
  */
 ssize_t posix_getline(char **restrict lineptr, size_t *restrict n,
     FILE *restrict stream)
 {
-        // TODO
-        not_implemented();
+        return posix_getdelim(lineptr, n, '\n', stream);
 }
 
@@ -421 +484 @@
  *     negative value on error.
  */
-int posix_sprintf(char *s, const char *format, ...)
+int posix_sprintf(char *s, const char *restrict format, ...)
 {
         va_list list;
@@ -439 +502 @@
  *     negative value on error.
  */
-int posix_vsprintf(char *s, const char *format, va_list ap)
+int posix_vsprintf(char *s, const char *restrict format, va_list ap)
 {
         return vsnprintf(s, STR_NO_LIMIT, format, ap);
@@ -461 +524 @@
 
 /**
- * Convert formatted input from the stream.
- * 
- * @param stream Input stream.
- * @param format Format description.
- * @param arg Output items.
- * @return The number of converted output items or EOF on failure.
- */
-int posix_vfscanf(FILE *restrict stream, const char *restrict format, va_list arg)
-{
-        // TODO
-        not_implemented();
-}
-
-/**
  * Convert formatted input from the standard input.
  * 
@@ -508 +557 @@
  * @return The number of converted output items or EOF on failure.
  */
-int posix_sscanf(const char *s, const char *format, ...)
+int posix_sscanf(const char *restrict s, const char *restrict format, ...)
 {
         va_list list;
@@ -518 +567 @@
 
 /**
- * Convert formatted input from the string.
- * 
- * @param s Input string.
- * @param format Format description.
- * @param arg Output items.
- * @return The number of converted output items or EOF on failure.
- */
-int posix_vsscanf(
-    const char *restrict s, const char *restrict format, va_list arg)
-{
-        // TODO
-        not_implemented();
-}
-
-/**
  * Acquire file stream for the thread.
  *