From: Ævar Arnfjörð Bjarmason Date: Sat, 14 May 2011 13:47:42 +0000 (+0000) Subject: git-sh-i18n--envsubst: our own envsubst(1) for eval_gettext() X-Git-Tag: v1.7.6-rc0~43^2~3 X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=ba67aaf2d05d1aa3def2b6eb1dc1d39bdf25bb41;p=git.git git-sh-i18n--envsubst: our own envsubst(1) for eval_gettext() Add a git-sh-i18n--envsubst program which is a stripped-down version of the GNU envsubst(1) program that comes with GNU gettext for use in the eval_gettext() fallback. We need a C helper program because implementing eval_gettext() purely in shell turned out to be unworkable. Digging through the Git mailing list archives will reveal two shell implementations of eval_gettext that are almost good enough, but fail on an edge case which is tested for in the tests which are part of this patch. These are the modifications I made to envsubst.c as I turned it into sh-i18n--envsubst.c: * Added our git-compat-util.h header for xrealloc() and friends. * Removed inclusion of gettext-specific headers. * Removed most of main() and replaced it with my own. The modified version only does option parsing for --variables. That's all it needs. * Modified error() invocations to use our error() instead of error(3). * Replaced the gettext XNMALLOC(n, size) macro with just xmalloc(n). Since XNMALLOC() only allocated char's. * Removed the string_list_destroy function. It's redundant (also in the upstream code). * Replaced the use of stdbool.h (a C99 header) by doing the following replacements on the code: * s/bool/unsigned short int/g * s/true/1/g * s/false/0/g Reported-by: Johannes Sixt Signed-off-by: Ævar Arnfjörð Bjarmason Signed-off-by: Junio C Hamano --- diff --git a/.gitignore b/.gitignore index 711fce7e0..1ccf79746 100644 --- a/.gitignore +++ b/.gitignore @@ -127,6 +127,8 @@ /git-rm /git-send-email /git-send-pack +/git-sh-i18n +/git-sh-i18n--envsubst /git-sh-setup /git-shell /git-shortlog diff --git a/Documentation/git-sh-i18n--envsubst.txt b/Documentation/git-sh-i18n--envsubst.txt new file mode 100644 index 000000000..f5bbf7750 --- /dev/null +++ b/Documentation/git-sh-i18n--envsubst.txt @@ -0,0 +1,26 @@ +git-sh-i18n--envsubst(1) +======================== + +NAME +---- +git-sh-i18n--envsubst - Git's own envsubst(1) for i18n fallbacks + +DESCRIPTION +----------- + +This is not a command the end user would want to run. Ever. +This documentation is meant for people who are studying the +plumbing scripts and/or are writing new ones. + +git-sh-i18n--envsubst is Git's stripped-down copy of the GNU +`envsubst(1)` program that comes with the GNU gettext package. It's +used internally by linkgit:git-sh-i18n[1] to interpolate the variables +passed to the the `eval_gettext` function. + +No promises are made about the interface, or that this +program won't disappear without warning in the next version +of Git. Don't use it. + +GIT +--- +Part of the linkgit:git[1] suite diff --git a/Makefile b/Makefile index ef57c1c9b..87c83cb45 100644 --- a/Makefile +++ b/Makefile @@ -414,6 +414,7 @@ PROGRAM_OBJS += shell.o PROGRAM_OBJS += show-index.o PROGRAM_OBJS += upload-pack.o PROGRAM_OBJS += http-backend.o +PROGRAM_OBJS += sh-i18n--envsubst.o PROGRAMS += $(patsubst %.o,git-%$X,$(PROGRAM_OBJS)) diff --git a/sh-i18n--envsubst.c b/sh-i18n--envsubst.c new file mode 100644 index 000000000..71250930d --- /dev/null +++ b/sh-i18n--envsubst.c @@ -0,0 +1,444 @@ +/* + * sh-i18n--envsubst.c - a stripped-down version of gettext's envsubst(1) + * + * Copyright (C) 2010 Ævar Arnfjörð Bjarmason + * + * This is a modified version of + * 67d0871a8c:gettext-runtime/src/envsubst.c from the gettext.git + * repository. It has been stripped down to only implement the + * envsubst(1) features that we need in the git-sh-i18n fallbacks. + * + * The "Close standard error" part in main() is from + * 8dac033df0:gnulib-local/lib/closeout.c. The copyright notices for + * both files are reproduced immediately below. + */ + +#include "git-compat-util.h" + +/* Substitution of environment variables in shell format strings. + Copyright (C) 2003-2007 Free Software Foundation, Inc. + Written by Bruno Haible , 2003. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software Foundation, + Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ + +/* closeout.c - close standard output and standard error + Copyright (C) 1998-2007 Free Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software Foundation, + Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ + +#include +#include +#include +#include +#include + +/* If true, substitution shall be performed on all variables. */ +static unsigned short int all_variables; + +/* Forward declaration of local functions. */ +static void print_variables (const char *string); +static void note_variables (const char *string); +static void subst_from_stdin (void); + +int +main (int argc, char *argv[]) +{ + /* Default values for command line options. */ + unsigned short int show_variables = 0; + + switch (argc) + { + case 1: + error ("we won't substitute all variables on stdin for you"); + /* + all_variables = 1; + subst_from_stdin (); + */ + case 2: + /* echo '$foo and $bar' | git sh-i18n--envsubst --variables '$foo and $bar' */ + all_variables = 0; + note_variables (argv[1]); + subst_from_stdin (); + break; + case 3: + /* git sh-i18n--envsubst --variables '$foo and $bar' */ + if (strcmp(argv[1], "--variables")) + error ("first argument must be --variables when two are given"); + show_variables = 1; + print_variables (argv[2]); + break; + default: + error ("too many arguments"); + break; + } + + /* Close standard error. This is simpler than fwriteerror_no_ebadf, because + upon failure we don't need an errno - all we can do at this point is to + set an exit status. */ + errno = 0; + if (ferror (stderr) || fflush (stderr)) + { + fclose (stderr); + exit (EXIT_FAILURE); + } + if (fclose (stderr) && errno != EBADF) + exit (EXIT_FAILURE); + + exit (EXIT_SUCCESS); +} + +/* Parse the string and invoke the callback each time a $VARIABLE or + ${VARIABLE} construct is seen, where VARIABLE is a nonempty sequence + of ASCII alphanumeric/underscore characters, starting with an ASCII + alphabetic/underscore character. + We allow only ASCII characters, to avoid dependencies w.r.t. the current + encoding: While "${\xe0}" looks like a variable access in ISO-8859-1 + encoding, it doesn't look like one in the BIG5, BIG5-HKSCS, GBK, GB18030, + SHIFT_JIS, JOHAB encodings, because \xe0\x7d is a single character in these + encodings. */ +static void +find_variables (const char *string, + void (*callback) (const char *var_ptr, size_t var_len)) +{ + for (; *string != '\0';) + if (*string++ == '$') + { + const char *variable_start; + const char *variable_end; + unsigned short int valid; + char c; + + if (*string == '{') + string++; + + variable_start = string; + c = *string; + if ((c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') || c == '_') + { + do + c = *++string; + while ((c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') + || (c >= '0' && c <= '9') || c == '_'); + variable_end = string; + + if (variable_start[-1] == '{') + { + if (*string == '}') + { + string++; + valid = 1; + } + else + valid = 0; + } + else + valid = 1; + + if (valid) + callback (variable_start, variable_end - variable_start); + } + } +} + + +/* Print a variable to stdout, followed by a newline. */ +static void +print_variable (const char *var_ptr, size_t var_len) +{ + fwrite (var_ptr, var_len, 1, stdout); + putchar ('\n'); +} + +/* Print the variables contained in STRING to stdout, each one followed by a + newline. */ +static void +print_variables (const char *string) +{ + find_variables (string, &print_variable); +} + + +/* Type describing list of immutable strings, + implemented using a dynamic array. */ +typedef struct string_list_ty string_list_ty; +struct string_list_ty +{ + const char **item; + size_t nitems; + size_t nitems_max; +}; + +/* Initialize an empty list of strings. */ +static inline void +string_list_init (string_list_ty *slp) +{ + slp->item = NULL; + slp->nitems = 0; + slp->nitems_max = 0; +} + +/* Append a single string to the end of a list of strings. */ +static inline void +string_list_append (string_list_ty *slp, const char *s) +{ + /* Grow the list. */ + if (slp->nitems >= slp->nitems_max) + { + size_t nbytes; + + slp->nitems_max = slp->nitems_max * 2 + 4; + nbytes = slp->nitems_max * sizeof (slp->item[0]); + slp->item = (const char **) xrealloc (slp->item, nbytes); + } + + /* Add the string to the end of the list. */ + slp->item[slp->nitems++] = s; +} + +/* Compare two strings given by reference. */ +static int +cmp_string (const void *pstr1, const void *pstr2) +{ + const char *str1 = *(const char **)pstr1; + const char *str2 = *(const char **)pstr2; + + return strcmp (str1, str2); +} + +/* Sort a list of strings. */ +static inline void +string_list_sort (string_list_ty *slp) +{ + if (slp->nitems > 0) + qsort (slp->item, slp->nitems, sizeof (slp->item[0]), cmp_string); +} + +/* Test whether a string list contains a given string. */ +static inline int +string_list_member (const string_list_ty *slp, const char *s) +{ + size_t j; + + for (j = 0; j < slp->nitems; ++j) + if (strcmp (slp->item[j], s) == 0) + return 1; + return 0; +} + +/* Test whether a sorted string list contains a given string. */ +static int +sorted_string_list_member (const string_list_ty *slp, const char *s) +{ + size_t j1, j2; + + j1 = 0; + j2 = slp->nitems; + if (j2 > 0) + { + /* Binary search. */ + while (j2 - j1 > 1) + { + /* Here we know that if s is in the list, it is at an index j + with j1 <= j < j2. */ + size_t j = (j1 + j2) >> 1; + int result = strcmp (slp->item[j], s); + + if (result > 0) + j2 = j; + else if (result == 0) + return 1; + else + j1 = j + 1; + } + if (j2 > j1) + if (strcmp (slp->item[j1], s) == 0) + return 1; + } + return 0; +} + + +/* Set of variables on which to perform substitution. + Used only if !all_variables. */ +static string_list_ty variables_set; + +/* Adds a variable to variables_set. */ +static void +note_variable (const char *var_ptr, size_t var_len) +{ + char *string = xmalloc (var_len + 1); + memcpy (string, var_ptr, var_len); + string[var_len] = '\0'; + + string_list_append (&variables_set, string); +} + +/* Stores the variables occurring in the string in variables_set. */ +static void +note_variables (const char *string) +{ + string_list_init (&variables_set); + find_variables (string, ¬e_variable); + string_list_sort (&variables_set); +} + + +static int +do_getc (void) +{ + int c = getc (stdin); + + if (c == EOF) + { + if (ferror (stdin)) + error ("error while reading standard input"); + } + + return c; +} + +static inline void +do_ungetc (int c) +{ + if (c != EOF) + ungetc (c, stdin); +} + +/* Copies stdin to stdout, performing substitutions. */ +static void +subst_from_stdin (void) +{ + static char *buffer; + static size_t bufmax; + static size_t buflen; + int c; + + for (;;) + { + c = do_getc (); + if (c == EOF) + break; + /* Look for $VARIABLE or ${VARIABLE}. */ + if (c == '$') + { + unsigned short int opening_brace = 0; + unsigned short int closing_brace = 0; + + c = do_getc (); + if (c == '{') + { + opening_brace = 1; + c = do_getc (); + } + if ((c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') || c == '_') + { + unsigned short int valid; + + /* Accumulate the VARIABLE in buffer. */ + buflen = 0; + do + { + if (buflen >= bufmax) + { + bufmax = 2 * bufmax + 10; + buffer = xrealloc (buffer, bufmax); + } + buffer[buflen++] = c; + + c = do_getc (); + } + while ((c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') + || (c >= '0' && c <= '9') || c == '_'); + + if (opening_brace) + { + if (c == '}') + { + closing_brace = 1; + valid = 1; + } + else + { + valid = 0; + do_ungetc (c); + } + } + else + { + valid = 1; + do_ungetc (c); + } + + if (valid) + { + /* Terminate the variable in the buffer. */ + if (buflen >= bufmax) + { + bufmax = 2 * bufmax + 10; + buffer = xrealloc (buffer, bufmax); + } + buffer[buflen] = '\0'; + + /* Test whether the variable shall be substituted. */ + if (!all_variables + && !sorted_string_list_member (&variables_set, buffer)) + valid = 0; + } + + if (valid) + { + /* Substitute the variable's value from the environment. */ + const char *env_value = getenv (buffer); + + if (env_value != NULL) + fputs (env_value, stdout); + } + else + { + /* Perform no substitution at all. Since the buffered input + contains no other '$' than at the start, we can just + output all the buffered contents. */ + putchar ('$'); + if (opening_brace) + putchar ('{'); + fwrite (buffer, buflen, 1, stdout); + if (closing_brace) + putchar ('}'); + } + } + else + { + do_ungetc (c); + putchar ('$'); + if (opening_brace) + putchar ('{'); + } + } + else + putchar (c); + } +} diff --git a/t/t0201-gettext-fallbacks.sh b/t/t0201-gettext-fallbacks.sh new file mode 100755 index 000000000..54d98b9b1 --- /dev/null +++ b/t/t0201-gettext-fallbacks.sh @@ -0,0 +1,51 @@ +#!/bin/sh +# +# Copyright (c) 2010 Ævar Arnfjörð Bjarmason +# + +test_description='Gettext Shell fallbacks' + +. ./test-lib.sh +. "$GIT_BUILD_DIR"/git-sh-i18n + +test_expect_success 'gettext: our gettext() fallback has pass-through semantics' ' + printf "test" >expect && + gettext "test" >actual && + test_i18ncmp expect actual && + printf "test more words" >expect && + gettext "test more words" >actual && + test_i18ncmp expect actual +' + +test_expect_success 'eval_gettext: our eval_gettext() fallback has pass-through semantics' ' + printf "test" >expect && + eval_gettext "test" >actual && + test_i18ncmp expect actual && + printf "test more words" >expect && + eval_gettext "test more words" >actual && + test_i18ncmp expect actual +' + +test_expect_success 'eval_gettext: our eval_gettext() fallback can interpolate variables' ' + printf "test YesPlease" >expect && + GIT_INTERNAL_GETTEXT_TEST_FALLBACKS=YesPlease eval_gettext "test \$GIT_INTERNAL_GETTEXT_TEST_FALLBACKS" >actual && + test_i18ncmp expect actual +' + +test_expect_success 'eval_gettext: our eval_gettext() fallback can interpolate variables with spaces' ' + cmdline="git am" && + export cmdline; + printf "When you have resolved this problem run git am --resolved." >expect && + eval_gettext "When you have resolved this problem run \$cmdline --resolved." >actual + test_i18ncmp expect actual +' + +test_expect_success 'eval_gettext: our eval_gettext() fallback can interpolate variables with spaces and quotes' ' + cmdline="git am" && + export cmdline; + printf "When you have resolved this problem run \"git am --resolved\"." >expect && + eval_gettext "When you have resolved this problem run \"\$cmdline --resolved\"." >actual + test_i18ncmp expect actual +' + +test_done