4 files changed, 95 insertions, 2 deletions

diff --git a/src/rt/rust.cpp b/src/rt/rust.cpp
index 9600b4d5..013705f2 100644
--- a/src/rt/rust.cpp
+++ b/src/rt/rust.cpp
@@ -80,6 +80,7 @@ extern "C" CDECL int
 rust_start(uintptr_t main_fn, rust_crate const *crate, int argc,
            char **argv) {
 
+    crate->update_log_settings(getenv("RUST_LOG"));
     rust_srv *srv = new rust_srv();
     rust_kernel *kernel = new rust_kernel(srv);
     kernel->start();
@@ -102,6 +103,7 @@ rust_start(uintptr_t main_fn, rust_crate const *crate, int argc,
     dom->root_task->start(crate->get_exit_task_glue(),
                           crate->abi_tag, main_fn,
                           (uintptr_t)&main_args, sizeof(main_args));
+
     int ret = dom->start_main_loop();
     delete args;
     kernel->destroy_domain(dom);
diff --git a/src/rt/rust_crate.cpp b/src/rt/rust_crate.cpp
index 23f01c07..e7ee0350 100644
--- a/src/rt/rust_crate.cpp
+++ b/src/rt/rust_crate.cpp
@@ -65,6 +65,92 @@ rust_crate::get_debug_abbrev(rust_dom *dom) const {
         return mem_area(dom, 0, 0);
 }
 
+struct mod_entry {
+    const char* name;
+    int* state;
+};
+
+struct cratemap {
+    mod_entry* entries;
+    cratemap* children[1];
+};
+
+struct log_directive {
+    char* name;
+    size_t level;
+};
+
+const size_t max_log_directives = 255;
+
+size_t parse_logging_spec(char* spec, log_directive* dirs) {
+    size_t dir = 0;
+    while (dir < max_log_directives && *spec) {
+        char* start = spec;
+        char cur;
+        while (true) {
+            cur = *spec;
+            if (cur == ',' || cur == '=' || cur == '\0') {
+                if (start == spec) {spec++; break;}
+                *spec = '\0';
+                spec++;
+                size_t level = 3;
+                if (cur == '=') {
+                    level = *spec - '0';
+                    if (level > 3) level = 1;
+                    if (*spec) ++spec;
+                }
+                dirs[dir].name = start;
+                dirs[dir++].level = level;
+                break;
+            }
+            spec++;
+        }
+    }
+    return dir;
+}
+
+void update_crate_map(cratemap* map, log_directive* dirs, size_t n_dirs) {
+    // First update log levels for this crate
+    for (mod_entry* cur = map->entries; cur->name; cur++) {
+        size_t level = 1, longest_match = 0;
+        for (size_t d = 0; d < n_dirs; d++) {
+            if (strstr(cur->name, dirs[d].name) == cur->name &&
+                strlen(dirs[d].name) > longest_match) {
+                longest_match = strlen(dirs[d].name);
+                level = dirs[d].level;
+            }
+        }
+        *cur->state = level;
+    }
+
+    // Then recurse on linked crates
+    for (size_t i = 0; map->children[i]; i++) {
+        update_crate_map(map->children[i], dirs, n_dirs);
+    }
+}
+
+void rust_crate::update_log_settings(char* settings) const {
+    // Only try this if the crate was generated by Rustc, not rustboot
+    if (image_base_off) return;
+
+    // This is a rather ugly parser for strings in the form
+    // "crate1,crate2.mod3,crate3.x=2". Log levels range 0=err, 1=warn,
+    // 2=info, 3=debug. Default is 1. Words without an '=X' part set the log
+    // level for that module (and submodules) to 3.
+    char* buffer = NULL;
+    log_directive dirs[256];
+    size_t dir = 0;
+    if (settings) {
+        buffer = (char*)malloc(strlen(settings));
+        strcpy(buffer, settings);
+        dir = parse_logging_spec(buffer, &dirs[0]);
+    }
+
+    update_crate_map((cratemap*)crate_map, &dirs[0], dir);
+
+    free(buffer);
+}
+
 //
 // Local Variables:
 // mode: C++
diff --git a/src/rt/rust_internal.h b/src/rt/rust_internal.h
index 4a1f3e45..695fc21d 100644
--- a/src/rt/rust_internal.h
+++ b/src/rt/rust_internal.h
@@ -248,6 +248,9 @@ public:
     size_t n_libs;
 
     uintptr_t abi_tag;
+    // FIXME: not generated by rustboot, should only be accessed in crates
+    // generated by rustc.
+    void* crate_map;
 
     // Crates are immutable, constructed by the compiler.
 
@@ -259,6 +262,8 @@ public:
     uintptr_t get_gc_glue() const;
     uintptr_t get_exit_task_glue() const;
 
+    void update_log_settings(char* settings) const;
+
     struct mem_area
     {
       rust_dom *dom;
diff --git a/src/rt/rust_log.cpp b/src/rt/rust_log.cpp
index 3017b549..076c4b0a 100644
--- a/src/rt/rust_log.cpp
+++ b/src/rt/rust_log.cpp
@@ -9,6 +9,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+// FIXME somehow unify this with the parsing happening in rust_crate.cpp
 static uint32_t
 read_type_bit_mask() {
     uint32_t bits = rust_log::ULOG | rust_log::ERR;
@@ -18,14 +19,13 @@ read_type_bit_mask() {
         str[0] = ',';
         strcpy(str + 1, env_str);
 
-        bits = 0;
+        bits = rust_log::ULOG;
         bits |= strstr(str, ",err") ? rust_log::ERR : 0;
         bits |= strstr(str, ",mem") ? rust_log::MEM : 0;
         bits |= strstr(str, ",comm") ? rust_log::COMM : 0;
         bits |= strstr(str, ",task") ? rust_log::TASK : 0;
         bits |= strstr(str, ",up") ? rust_log::UPCALL : 0;
         bits |= strstr(str, ",dom") ? rust_log::DOM : 0;
-        bits |= strstr(str, ",ulog") ? rust_log::ULOG : 0;
         bits |= strstr(str, ",trace") ? rust_log::TRACE : 0;
         bits |= strstr(str, ",dwarf") ? rust_log::DWARF : 0;
         bits |= strstr(str, ",cache") ? rust_log::CACHE : 0;