Changeset 3621 in MondoRescue for branches/3.3/mindi-busybox/applets/applet_tables.c

Timestamp:

Dec 20, 2016, 4:07:32 PM (7 years ago)

Author:

Bruno Cornec

Message:

New 3?3 banch for incorporation of latest busybox 1.25. Changing minor version to handle potential incompatibilities.

Location:

branches/3.3

Files:

• . (copied) (copied from branches/3.2 )
• mindi-busybox/applets/applet_tables.c (modified) (7 diffs)

branches/3.3/mindi-busybox/applets/applet_tables.c

@@ -15 +15 @@
 #include <stdio.h>
 #include <unistd.h>
+#include <ctype.h>
 
 #undef ARRAY_SIZE
@@ -41 +42 @@
 enum { NUM_APPLETS = ARRAY_SIZE(applets) };
 
-static int offset[NUM_APPLETS];
-
 static int cmp_name(const void *a, const void *b)
 {
@@ -50 +49 @@
 }
 
+static int str_isalnum_(const char *s)
+{
+    while (*s) {
+        if (!isalnum(*s) && *s != '_')
+            return 0;
+        s++;
+    }
+    return 1;
+}
+
 int main(int argc, char **argv)
 {
-    int i;
-    int ofs;
-    unsigned MAX_APPLET_NAME_LEN = 1;
+    int i, j;
+
+    // In find_applet_by_name(), before linear search, narrow it down
+    // by looking at N "equidistant" names. With ~350 applets:
+    // KNOWN_APPNAME_OFFSETS  cycles
+    //                     0    9057
+    //                     2    4604 + ~100 bytes of code
+    //                     4    2407 + 4 bytes
+    //                     8    1342 + 8 bytes
+    //                    16     908 + 16 bytes
+    //                    32     884 + 32 bytes
+    // With 8, int16_t applet_nameofs[] table has 7 elements.
+    int KNOWN_APPNAME_OFFSETS = 8;
+    // With 128 applets we do two linear searches, with 1..7 strcmp's in the first one
+    // and 1..16 strcmp's in the second. With 256 apps, second search does 1..32 strcmp's.
+    if (NUM_APPLETS < 128)
+        KNOWN_APPNAME_OFFSETS = 4;
+    if (NUM_APPLETS < 32)
+        KNOWN_APPNAME_OFFSETS = 0;
 
     qsort(applets, NUM_APPLETS, sizeof(applets[0]), cmp_name);
 
-    ofs = 0;
-    for (i = 0; i < NUM_APPLETS; i++) {
-        offset[i] = ofs;
-        ofs += strlen(applets[i].name) + 1;
-    }
-    /* We reuse 4 high-order bits of offset array for other purposes,
-     * so if they are indeed needed, refuse to proceed */
-    if (ofs > 0xfff)
-        return 1;
     if (!argv[1])
         return 1;
-
     i = open(argv[1], O_WRONLY | O_TRUNC | O_CREAT, 0666);
     if (i < 0)
@@ -84 +99 @@
         printf("#define SINGLE_APPLET_MAIN %s_main\n", applets[0].main);
     }
-    printf("\n");
+
+    printf("#define KNOWN_APPNAME_OFFSETS %u\n\n", KNOWN_APPNAME_OFFSETS);
+    if (KNOWN_APPNAME_OFFSETS > 0) {
+        int ofs, offset[KNOWN_APPNAME_OFFSETS], index[KNOWN_APPNAME_OFFSETS];
+        for (i = 0; i < KNOWN_APPNAME_OFFSETS; i++)
+            index[i] = i * NUM_APPLETS / KNOWN_APPNAME_OFFSETS;
+        ofs = 0;
+        for (i = 0; i < NUM_APPLETS; i++) {
+            for (j = 0; j < KNOWN_APPNAME_OFFSETS; j++)
+                if (i == index[j])
+                    offset[j] = ofs;
+            ofs += strlen(applets[i].name) + 1;
+        }
+        /* If the list of names is too long refuse to proceed */
+        if (ofs > 0xffff)
+            return 1;
+        printf("const uint16_t applet_nameofs[] ALIGN2 = {\n");
+        for (i = 1; i < KNOWN_APPNAME_OFFSETS; i++)
+            printf("%d,\n", offset[i]);
+        printf("};\n\n");
+    }
 
     //printf("#ifndef SKIP_definitions\n");
@@ -90 +125 @@
     for (i = 0; i < NUM_APPLETS; i++) {
         printf("\"%s\" \"\\0\"\n", applets[i].name);
-        if (MAX_APPLET_NAME_LEN < strlen(applets[i].name))
-            MAX_APPLET_NAME_LEN = strlen(applets[i].name);
+//      if (MAX_APPLET_NAME_LEN < strlen(applets[i].name))
+//          MAX_APPLET_NAME_LEN = strlen(applets[i].name);
     }
     printf(";\n\n");
+
+    for (i = 0; i < NUM_APPLETS; i++) {
+        if (str_isalnum_(applets[i].name))
+            printf("#define APPLET_NO_%s %d\n", applets[i].name, i);
+    }
+    printf("\n");
 
     printf("#ifndef SKIP_applet_main\n");
@@ -103 +144 @@
     printf("#endif\n\n");
 
-    printf("const uint16_t applet_nameofs[] ALIGN2 = {\n");
-    for (i = 0; i < NUM_APPLETS; i++) {
-        printf("0x%04x,\n",
-            offset[i]
 #if ENABLE_FEATURE_PREFER_APPLETS
-            + (applets[i].nofork << 12)
-            + (applets[i].noexec << 13)
+    printf("const uint8_t applet_flags[] ALIGN1 = {\n");
+    i = 0;
+    while (i < NUM_APPLETS) {
+        int v = applets[i].nofork + (applets[i].noexec << 1);
+        if (++i < NUM_APPLETS)
+            v |= (applets[i].nofork + (applets[i].noexec << 1)) << 2;
+        if (++i < NUM_APPLETS)
+            v |= (applets[i].nofork + (applets[i].noexec << 1)) << 4;
+        if (++i < NUM_APPLETS)
+            v |= (applets[i].nofork + (applets[i].noexec << 1)) << 6;
+        printf("0x%02x,\n", v);
+        i++;
+    }
+    printf("};\n\n");
 #endif
+
 #if ENABLE_FEATURE_SUID
-            + (applets[i].need_suid << 14) /* 2 bits */
+    printf("const uint8_t applet_suid[] ALIGN1 = {\n");
+    i = 0;
+    while (i < NUM_APPLETS) {
+        int v = applets[i].need_suid; /* 2 bits */
+        if (++i < NUM_APPLETS)
+            v |= applets[i].need_suid << 2;
+        if (++i < NUM_APPLETS)
+            v |= applets[i].need_suid << 4;
+        if (++i < NUM_APPLETS)
+            v |= applets[i].need_suid << 6;
+        printf("0x%02x,\n", v);
+        i++;
+    }
+    printf("};\n\n");
 #endif
-        );
-    }
-    printf("};\n\n");
 
 #if ENABLE_FEATURE_INSTALLER
@@ -131 +191 @@
 #endif
     //printf("#endif /* SKIP_definitions */\n");
-    printf("\n");
-    printf("#define MAX_APPLET_NAME_LEN %u\n", MAX_APPLET_NAME_LEN);
+//  printf("\n");
+//  printf("#define MAX_APPLET_NAME_LEN %u\n", MAX_APPLET_NAME_LEN);
 
     if (argv[2]) {