fastbootd: userspace implementation of the fastboot device-side protocol

Initial commit of fastbootd.  A few commands work, but not
fully functional yet.

Change-Id: I589dee7b327b4460e94b4434aaf9bcf780faa839
diff --git a/fastbootd/config.c b/fastbootd/config.c
new file mode 100644
index 0000000..b8503fd
--- /dev/null
+++ b/fastbootd/config.c
@@ -0,0 +1,161 @@
+/*
+ * Copyright (c) 2013, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *  * Neither the name of Google, Inc. nor the names of its contributors
+ *    may be used to endorse or promote products derived from this
+ *    software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <fcntl.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+
+#include "protocol.h"
+
+#include "debug.h"
+
+// TODO: change config path
+#define CONFIG_PATH "/data/fastboot.cfg"
+
+static char *strip(char *str)
+{
+    int n;
+
+    n = strspn(str, " \t");
+    str += n;
+
+    for (n = strlen(str) - 1; n >= 0; n--) {
+        if (str[n] == ' ' || str[n] == '\t')
+            str[n] = '\0';
+        else
+            break;
+    }
+
+    return str;
+}
+
+static int config_parse_line(char *line)
+{
+    char *c;
+    char *key;
+    char *value;
+
+    c = strchr(line, '#');
+    if (c)
+        *c = '\0';
+
+    if (strspn(line, " \t") == strlen(line))
+        return 0;
+
+    c = strchr(line, '=');
+    if (c == NULL)
+        return -1;
+
+    key = line;
+    *c = '\0';
+    value = c + 1;
+
+    key = strip(key);
+    value = strip(value);
+
+    key = strdup(key);
+    value = strdup(value);
+
+    fastboot_publish(key, value);
+
+    return 0;
+}
+
+static void config_parse(char *buffer)
+{
+    char *saveptr;
+    char *str = buffer;
+    char *line = buffer;
+    int c;
+    int ret;
+
+    for (c = 1; line != NULL; c++) {
+        line = strtok_r(str, "\r\n", &saveptr);
+        if (line != NULL) {
+            D(VERBOSE, "'%s'", line);
+            ret = config_parse_line(line);
+            if (ret < 0) {
+                D(WARN, "error parsing " CONFIG_PATH " line %d", c);
+            }
+        }
+        str = NULL;
+    }
+}
+
+void config_init()
+{
+    int fd;
+    off_t len;
+    ssize_t ret;
+    size_t count = 0;
+    char *buffer;
+
+    fd = open(CONFIG_PATH, O_RDONLY);
+    if (fd < 0) {
+        D(ERR, "failed to open " CONFIG_PATH);
+        return;
+    }
+
+    len = lseek(fd, 0, SEEK_END);
+    if (len < 0) {
+        D(ERR, "failed to seek to end of " CONFIG_PATH);
+        return;
+    }
+
+    lseek(fd, 0, SEEK_SET);
+
+    buffer = malloc(len + 1);
+    if (buffer == NULL) {
+        D(ERR, "failed to allocate %ld bytes", len);
+        return;
+    }
+
+    while (count < (size_t)len) {
+        ret = read(fd, buffer + count, len - count);
+        if (ret < 0 && errno != EINTR) {
+            D(ERR, "failed to read " CONFIG_PATH ": %d %s", errno, strerror(errno));
+            return;
+        }
+        if (ret == 0) {
+            D(ERR, "early EOF reading " CONFIG_PATH);
+            return;
+        }
+
+        count += ret;
+    }
+
+    buffer[len] = '\0';
+
+    config_parse(buffer);
+
+    free(buffer);
+}