makedevs: support using user/group names in device table files

Compared to hard coding the numeric group and user ids in the device
table files, the way of using user/group names is preferred.

This patch adds the ability to makedevs to correctly deal with device
table files with user/group names in them.

To maintain backward compatibility, the way of using uid/gid is still
supported.

[YOCTO #1159]

(From OE-Core rev: 1fcf718e3a1e50446ab61972069566e5016bc625)

Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
Signed-off-by: Saul Wold <sgw@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 178 insertions, 29 deletions

diff --git a/meta/recipes-devtools/makedevs/makedevs-1.0.0/makedevs.c b/meta/recipes-devtools/makedevs/makedevs-1.0.0/makedevs.c
index 6c1f2fb461..cc3707b2c8 100644
--- a/meta/recipes-devtools/makedevs/makedevs-1.0.0/makedevs.c
+++ b/meta/recipes-devtools/makedevs/makedevs-1.0.0/makedevs.c
@@ -16,6 +16,11 @@
 
 #define MINORBITS       8
 #define MKDEV(ma,mi)    (((ma) << MINORBITS) | (mi))
+#define MAX_ID_LEN      40
+#define MAX_NAME_LEN    40
+#ifndef PATH_MAX
+#define PATH_MAX        4096
+#endif
 
 /* These are all stolen from busybox's libbb to make
  * error handling simpler (and since I maintain busybox, 
@@ -27,6 +32,15 @@ static const char *const memory_exhausted = "memory exhausted";
 static char default_rootdir[]=".";
 static char *rootdir = default_rootdir;
 
+struct name_id {
+        char name[MAX_NAME_LEN+1];
+        unsigned long id;
+        struct name_id *next;
+};
+
+static struct name_id *usr_list = NULL;
+static struct name_id *grp_list = NULL;
+
 static void verror_msg(const char *s, va_list p)
 {
         fflush(stdout);
@@ -57,17 +71,6 @@ static void vperror_msg(const char *s, va_list p)
         fprintf(stderr, "%s%s\n", s, strerror(err));
 }
 
-#if 0
-static void perror_msg(const char *s, ...)
-{
-        va_list p;
-
-        va_start(p, s);
-        vperror_msg(s, p);
-        va_end(p);
-}
-#endif
-
 static void perror_msg_and_die(const char *s, ...)
 {
         va_list p;
@@ -102,6 +105,124 @@ static char *xstrdup(const char *s)
         return t;
 }
 
+static struct name_id* alloc_node(void)
+{
+        struct name_id *node;
+        node = (struct name_id*)malloc(sizeof(struct name_id));
+        if (node == NULL) {
+                error_msg_and_die(memory_exhausted);
+        }
+        memset((void *)node->name, 0, MAX_NAME_LEN+1);
+        node->id = 0xffffffff;
+        node->next = NULL;
+        return node;
+}
+
+static struct name_id* parse_line(char *line)
+{
+        char *p;
+        int i;
+        char id_buf[MAX_ID_LEN+1];
+        struct name_id *node;
+        node = alloc_node();
+        p = line;
+        i = 0;
+        // Get name field
+        while (*p != ':') {
+                if (i > MAX_NAME_LEN)
+                        error_msg_and_die("Name field too long");
+                node->name[i++] = *p++;
+        }
+        node->name[i] = '\0';
+        p++;
+        // Skip the second field
+        while (*p != ':')
+                p++;
+        p++;
+        // Get id field
+        i = 0;
+        while (*p != ':') {
+                if (i > MAX_ID_LEN)
+                        error_msg_and_die("ID filed too long");
+                id_buf[i++] = *p++;
+        }
+        id_buf[i] = '\0';
+        node->id = atol(id_buf);
+        return node;
+}
+
+static void get_list_from_file(FILE *file, struct name_id **plist)
+{
+        char *line;
+        int len = 0;
+        size_t length = 256;
+        struct name_id *node, *cur;
+
+        if((line = (char *)malloc(length)) == NULL) {
+                error_msg_and_die(memory_exhausted);
+        }
+
+        while ((len = getline(&line, &length, file)) != -1) {
+                node = parse_line(line);
+                if (*plist == NULL) {
+                        *plist = node;
+                        cur = *plist;
+                } else {
+                        cur->next = node;
+                        cur = cur->next;
+                }
+        }
+
+        if (line)
+                free(line);
+}
+
+static unsigned long convert2guid(char *id_buf, struct name_id *search_list)
+{
+        char *p;
+        int isnum;
+        struct name_id *node;
+        p = id_buf;
+        isnum = 1;
+        while (*p != '\0') {
+                if (!isdigit(*p)) {
+                        isnum = 0;
+                        break;
+                }
+                p++;
+        }
+        if (isnum) {
+                // Check for bad user/group name
+                node = search_list;
+                while (node != NULL) {
+                        if (!strncmp(node->name, id_buf, strlen(id_buf))) {
+                                fprintf(stderr, "WARNING: Bad user/group name %s detected\n", id_buf);
+                                break;
+                        }
+                        node = node->next;
+                }
+                return (unsigned long)atol(id_buf);
+        } else {
+                node = search_list;
+                while (node != NULL) {
+                        if (!strncmp(node->name, id_buf, strlen(id_buf)))
+                                return node->id;
+                        node = node->next;
+                }
+                error_msg_and_die("No entry for %s in search list", id_buf);
+        }
+}
+
+static void free_list(struct name_id *list)
+{
+        struct name_id *cur;
+        cur = list;
+        while (cur != NULL) {
+                list = cur;
+                cur = cur->next;
+                free(list);
+        }
+}
 
 static void add_new_directory(char *name, char *path, 
                 unsigned long uid, unsigned long gid, unsigned long mode)
@@ -162,8 +283,9 @@ static void add_new_fifo(char *name, char *path, unsigned long uid,
 
 
 /*  device table entries take the form of:
-    <path>      <type> <mode>   <uid>   <gid>   <major> <minor> <start> <inc>   <count>
+    <path>      <type> <mode>   <usr>   <grp>   <major> <minor> <start> <inc>   <count>
     /dev/mem    c      640      0       0       1       1       0        0        -
+    /dev/zero   c      644      root    root    1       5       -        -        -
 
     type can be one of: 
         f       A regular file
@@ -181,18 +303,23 @@ static void add_new_fifo(char *name, char *path, unsigned long uid,
 static int interpret_table_entry(char *line)
 {
         char *name;
+        char usr_buf[MAX_ID_LEN];
+        char grp_buf[MAX_ID_LEN];
         char path[4096], type;
         unsigned long mode = 0755, uid = 0, gid = 0, major = 0, minor = 0;
         unsigned long start = 0, increment = 1, count = 0;
 
-        if (0 > sscanf(line, "%40s %c %lo %lu %lu %lu %lu %lu %lu %lu", path,
-                    &type, &mode, &uid, &gid, &major, &minor, &start,
+        if (0 > sscanf(line, "%40s %c %lo %40s %40s %lu %lu %lu %lu %lu", path,
+                    &type, &mode, usr_buf, grp_buf, &major, &minor, &start,
                     &increment, &count)) 
         {
                 return 1;
         }
 
-        if (!strcmp(path, "/")) {
+        uid = convert2guid(usr_buf, usr_list);
+        gid = convert2guid(grp_buf, grp_list);
+
+        if (strncmp(path, "/", 1)) {
                 error_msg_and_die("Device table entries require absolute paths");
         }
         name = xstrdup(path + 1);
@@ -231,7 +358,6 @@ static int interpret_table_entry(char *line)
                         /* FIXME:  MKDEV uses illicit insider knowledge of kernel 
                          * major/minor representation...  */
                         dev_t rdev = MKDEV(major, minor);
-
                         add_new_device(name, path, uid, gid, mode, rdev);
                 }
                 break;
@@ -249,17 +375,15 @@ static void parse_device_table(FILE * file)
         size_t length = 256;
         int len = 0;
 
+        if((line = (char *)malloc(length)) == NULL) {
+                error_msg_and_die(memory_exhausted);
+        }
         /* Looks ok so far.  The general plan now is to read in one
          * line at a time, check for leading comment delimiters ('#'),
          * then try and parse the line as a device table.  If we fail
          * to parse things, try and help the poor fool to fix their
          * device table with a useful error msg... */
 
-        if((line = (char *)malloc(length)) == NULL) {
-                fclose(file);
-                return;
-        }
-
         while ((len = getline(&line, &length, file)) != -1) {
                 /* First trim off any whitespace */
 
@@ -273,20 +397,20 @@ static void parse_device_table(FILE * file)
                 /* If this is NOT a comment line, try to interpret it */
                 if (*line != '#') interpret_table_entry(line);
         }
-        if (line) free(line);
 
-        fclose(file);
+        if (line)
+                free(line);
 }
 
-static int go(char *dname, FILE * devtable)
+static int parse_devtable(FILE * devtable)
 {
         struct stat sb;
 
-        if (lstat(dname, &sb)) {
-                perror_msg_and_die("%s", dname);
+        if (lstat(rootdir, &sb)) {
+                perror_msg_and_die("%s", rootdir);
         }
-        if (chdir(dname))
-                perror_msg_and_die("%s", dname);
+        if (chdir(rootdir))
+                perror_msg_and_die("%s", rootdir);
 
         if (devtable)
                 parse_device_table(devtable);
@@ -322,6 +446,10 @@ int main(int argc, char **argv)
         int c, opt;
         extern char *optarg;
         struct stat statbuf;
+        char passwd_path[PATH_MAX];
+        char group_path[PATH_MAX];
+        FILE *passwd_file = NULL;
+        FILE *group_file = NULL;
         FILE *devtable = NULL;
 
         umask (0);
@@ -354,6 +482,27 @@ int main(int argc, char **argv)
                 }
         }
 
-        go(rootdir, devtable);
+        // Get name-id mapping
+        sprintf(passwd_path, "%s/etc/passwd", rootdir);
+        sprintf(group_path, "%s/etc/group", rootdir);
+        if ((passwd_file = fopen(passwd_path, "r")) != NULL) {
+                get_list_from_file(passwd_file, &usr_list);
+                fclose(passwd_file);
+        }
+        if ((group_file = fopen(group_path, "r")) != NULL) {
+                get_list_from_file(group_file, &grp_list);
+                fclose(group_file);
+        }
+
+        // Parse devtable
+        if(devtable) {
+                parse_devtable(devtable);
+                fclose(devtable);
+        }
+
+        // Free list
+        free_list(usr_list);
+        free_list(grp_list);
+
         return 0;
 }