py: Allow lexer to raise exceptions during construction.
This patch refactors the error handling in the lexer, to simplify it (ie
reduce code size).
A long time ago, when the lexer/parser/compiler were first written, the
lexer and parser were designed so they didn't use exceptions (ie nlr) to
report errors but rather returned an error code. Over time that has
gradually changed, the parser in particular has more and more ways of
raising exceptions. Also, the lexer never really handled all errors without
raising, eg there were some memory errors which could raise an exception
(and in these rare cases one would get a fatal nlr-not-handled fault).
This patch accepts the fact that the lexer can raise exceptions in some
cases and allows it to raise exceptions to handle all its errors, which are
for the most part just out-of-memory errors during construction of the
lexer. This makes the lexer a bit simpler, and also the persistent code
stuff is simplified.
What this means for users of the lexer is that calls to it must be wrapped
in a nlr handler. But all uses of the lexer already have such an nlr
handler for the parser (and compiler) so that doesn't put any extra burden
on the callers.
diff --git a/extmod/vfs_reader.c b/extmod/vfs_reader.c
index 9509582..891098a 100644
--- a/extmod/vfs_reader.c
+++ b/extmod/vfs_reader.c
@@ -27,7 +27,7 @@
#include <stdio.h>
#include <string.h>
-#include "py/nlr.h"
+#include "py/runtime.h"
#include "py/stream.h"
#include "py/reader.h"
#include "extmod/vfs.h"
@@ -69,30 +69,19 @@
m_del_obj(mp_reader_vfs_t, reader);
}
-int mp_reader_new_file(mp_reader_t *reader, const char *filename) {
- mp_reader_vfs_t *rf = m_new_obj_maybe(mp_reader_vfs_t);
- if (rf == NULL) {
- return MP_ENOMEM;
- }
- // TODO we really should just let this function raise a uPy exception
- nlr_buf_t nlr;
- if (nlr_push(&nlr) == 0) {
- mp_obj_t arg = mp_obj_new_str(filename, strlen(filename), false);
- rf->file = mp_vfs_open(1, &arg, (mp_map_t*)&mp_const_empty_map);
- int errcode;
- rf->len = mp_stream_rw(rf->file, rf->buf, sizeof(rf->buf), &errcode, MP_STREAM_RW_READ | MP_STREAM_RW_ONCE);
- nlr_pop();
- if (errcode != 0) {
- return errcode;
- }
- } else {
- return MP_ENOENT; // assume error was "file not found"
+void mp_reader_new_file(mp_reader_t *reader, const char *filename) {
+ mp_reader_vfs_t *rf = m_new_obj(mp_reader_vfs_t);
+ mp_obj_t arg = mp_obj_new_str(filename, strlen(filename), false);
+ rf->file = mp_vfs_open(1, &arg, (mp_map_t*)&mp_const_empty_map);
+ int errcode;
+ rf->len = mp_stream_rw(rf->file, rf->buf, sizeof(rf->buf), &errcode, MP_STREAM_RW_READ | MP_STREAM_RW_ONCE);
+ if (errcode != 0) {
+ mp_raise_OSError(errcode);
}
rf->pos = 0;
reader->data = rf;
reader->readbyte = mp_reader_vfs_readbyte;
reader->close = mp_reader_vfs_close;
- return 0; // success
}
#endif // MICROPY_READER_VFS
diff --git a/py/builtinevex.c b/py/builtinevex.c
index 636f869..b0514ee 100644
--- a/py/builtinevex.c
+++ b/py/builtinevex.c
@@ -136,9 +136,6 @@
mp_lexer_t *lex;
if (MICROPY_PY_BUILTINS_EXECFILE && parse_input_kind == MP_PARSE_SINGLE_INPUT) {
lex = mp_lexer_new_from_file(str);
- if (lex == NULL) {
- nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_OSError, "could not open file '%s'", str));
- }
parse_input_kind = MP_PARSE_FILE_INPUT;
} else {
lex = mp_lexer_new_from_str_len(MP_QSTR__lt_string_gt_, str, str_len, 0);
diff --git a/py/builtinimport.c b/py/builtinimport.c
index 0a917c6..96846b9 100644
--- a/py/builtinimport.c
+++ b/py/builtinimport.c
@@ -131,18 +131,7 @@
}
#if MICROPY_ENABLE_COMPILER
-STATIC void do_load_from_lexer(mp_obj_t module_obj, mp_lexer_t *lex, const char *fname) {
-
- if (lex == NULL) {
- // we verified the file exists using stat, but lexer could still fail
- if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
- mp_raise_msg(&mp_type_ImportError, "module not found");
- } else {
- nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ImportError,
- "no module named '%s'", fname));
- }
- }
-
+STATIC void do_load_from_lexer(mp_obj_t module_obj, mp_lexer_t *lex) {
#if MICROPY_PY___FILE__
qstr source_name = lex->source_name;
mp_store_attr(module_obj, MP_QSTR___file__, MP_OBJ_NEW_QSTR(source_name));
@@ -207,7 +196,7 @@
// found the filename in the list of frozen files, then load and execute it.
#if MICROPY_MODULE_FROZEN_STR
if (frozen_type == MP_FROZEN_STR) {
- do_load_from_lexer(module_obj, modref, file_str);
+ do_load_from_lexer(module_obj, modref);
return;
}
#endif
@@ -235,7 +224,7 @@
#if MICROPY_ENABLE_COMPILER
{
mp_lexer_t *lex = mp_lexer_new_from_file(file_str);
- do_load_from_lexer(module_obj, lex, file_str);
+ do_load_from_lexer(module_obj, lex);
return;
}
#endif
diff --git a/py/lexer.c b/py/lexer.c
index 9dcdd19..fadaee6 100644
--- a/py/lexer.c
+++ b/py/lexer.c
@@ -699,13 +699,7 @@
}
mp_lexer_t *mp_lexer_new(qstr src_name, mp_reader_t reader) {
- mp_lexer_t *lex = m_new_obj_maybe(mp_lexer_t);
-
- // check for memory allocation error
- if (lex == NULL) {
- reader.close(reader.data);
- return NULL;
- }
+ mp_lexer_t *lex = m_new_obj(mp_lexer_t);
lex->source_name = src_name;
lex->reader = reader;
@@ -715,16 +709,9 @@
lex->nested_bracket_level = 0;
lex->alloc_indent_level = MICROPY_ALLOC_LEXER_INDENT_INIT;
lex->num_indent_level = 1;
- lex->indent_level = m_new_maybe(uint16_t, lex->alloc_indent_level);
+ lex->indent_level = m_new(uint16_t, lex->alloc_indent_level);
vstr_init(&lex->vstr, 32);
- // check for memory allocation error
- // note: vstr_init above may fail on malloc, but so may mp_lexer_to_next below
- if (lex->indent_level == NULL) {
- mp_lexer_free(lex);
- return NULL;
- }
-
// store sentinel for first indentation level
lex->indent_level[0] = 0;
@@ -764,9 +751,7 @@
mp_lexer_t *mp_lexer_new_from_str_len(qstr src_name, const char *str, size_t len, size_t free_len) {
mp_reader_t reader;
- if (!mp_reader_new_mem(&reader, (const byte*)str, len, free_len)) {
- return NULL;
- }
+ mp_reader_new_mem(&reader, (const byte*)str, len, free_len);
return mp_lexer_new(src_name, reader);
}
@@ -774,10 +759,7 @@
mp_lexer_t *mp_lexer_new_from_file(const char *filename) {
mp_reader_t reader;
- int ret = mp_reader_new_file(&reader, filename);
- if (ret != 0) {
- return NULL;
- }
+ mp_reader_new_file(&reader, filename);
return mp_lexer_new(qstr_from_str(filename), reader);
}
@@ -785,10 +767,7 @@
mp_lexer_t *mp_lexer_new_from_fd(qstr filename, int fd, bool close_fd) {
mp_reader_t reader;
- int ret = mp_reader_new_file_from_fd(&reader, fd, close_fd);
- if (ret != 0) {
- return NULL;
- }
+ mp_reader_new_file_from_fd(&reader, fd, close_fd);
return mp_lexer_new(filename, reader);
}
diff --git a/py/persistentcode.c b/py/persistentcode.c
index 5cb5117..2a9a5b7 100644
--- a/py/persistentcode.c
+++ b/py/persistentcode.c
@@ -225,18 +225,13 @@
mp_raw_code_t *mp_raw_code_load_mem(const byte *buf, size_t len) {
mp_reader_t reader;
- if (!mp_reader_new_mem(&reader, buf, len, 0)) {
- m_malloc_fail(BYTES_PER_WORD); // we need to raise a MemoryError
- }
+ mp_reader_new_mem(&reader, buf, len, 0);
return mp_raw_code_load(&reader);
}
mp_raw_code_t *mp_raw_code_load_file(const char *filename) {
mp_reader_t reader;
- int ret = mp_reader_new_file(&reader, filename);
- if (ret != 0) {
- mp_raise_OSError(ret);
- }
+ mp_reader_new_file(&reader, filename);
return mp_raw_code_load(&reader);
}
diff --git a/py/reader.c b/py/reader.c
index d7de7aa..5df45c4 100644
--- a/py/reader.c
+++ b/py/reader.c
@@ -27,6 +27,7 @@
#include <stdio.h>
#include <assert.h>
+#include "py/runtime.h"
#include "py/mperrno.h"
#include "py/reader.h"
@@ -54,11 +55,8 @@
m_del_obj(mp_reader_mem_t, reader);
}
-bool mp_reader_new_mem(mp_reader_t *reader, const byte *buf, size_t len, size_t free_len) {
- mp_reader_mem_t *rm = m_new_obj_maybe(mp_reader_mem_t);
- if (rm == NULL) {
- return false;
- }
+void mp_reader_new_mem(mp_reader_t *reader, const byte *buf, size_t len, size_t free_len) {
+ mp_reader_mem_t *rm = m_new_obj(mp_reader_mem_t);
rm->free_len = free_len;
rm->beg = buf;
rm->cur = buf;
@@ -66,7 +64,6 @@
reader->data = rm;
reader->readbyte = mp_reader_mem_readbyte;
reader->close = mp_reader_mem_close;
- return true;
}
#if MICROPY_READER_POSIX
@@ -110,14 +107,8 @@
m_del_obj(mp_reader_posix_t, reader);
}
-int mp_reader_new_file_from_fd(mp_reader_t *reader, int fd, bool close_fd) {
- mp_reader_posix_t *rp = m_new_obj_maybe(mp_reader_posix_t);
- if (rp == NULL) {
- if (close_fd) {
- close(fd);
- }
- return MP_ENOMEM;
- }
+void mp_reader_new_file_from_fd(mp_reader_t *reader, int fd, bool close_fd) {
+ mp_reader_posix_t *rp = m_new_obj(mp_reader_posix_t);
rp->close_fd = close_fd;
rp->fd = fd;
int n = read(rp->fd, rp->buf, sizeof(rp->buf));
@@ -125,22 +116,21 @@
if (close_fd) {
close(fd);
}
- return errno;
+ mp_raise_OSError(errno);
}
rp->len = n;
rp->pos = 0;
reader->data = rp;
reader->readbyte = mp_reader_posix_readbyte;
reader->close = mp_reader_posix_close;
- return 0; // success
}
-int mp_reader_new_file(mp_reader_t *reader, const char *filename) {
+void mp_reader_new_file(mp_reader_t *reader, const char *filename) {
int fd = open(filename, O_RDONLY, 0644);
if (fd < 0) {
- return errno;
+ mp_raise_OSError(errno);
}
- return mp_reader_new_file_from_fd(reader, fd, true);
+ mp_reader_new_file_from_fd(reader, fd, true);
}
#endif
diff --git a/py/reader.h b/py/reader.h
index b02d961..8511c72 100644
--- a/py/reader.h
+++ b/py/reader.h
@@ -39,8 +39,8 @@
void (*close)(void *data);
} mp_reader_t;
-bool mp_reader_new_mem(mp_reader_t *reader, const byte *buf, size_t len, size_t free_len);
-int mp_reader_new_file(mp_reader_t *reader, const char *filename);
-int mp_reader_new_file_from_fd(mp_reader_t *reader, int fd, bool close_fd);
+void mp_reader_new_mem(mp_reader_t *reader, const byte *buf, size_t len, size_t free_len);
+void mp_reader_new_file(mp_reader_t *reader, const char *filename);
+void mp_reader_new_file_from_fd(mp_reader_t *reader, int fd, bool close_fd);
#endif // MICROPY_INCLUDED_PY_READER_H